Given :
An electron with kinetic energy of 3 MeV.
To Find :
The de-Broglie wavelength for that electron.
Solution :
We know, de-Broglie wavelength for an electron with kinetic energy K.E is given by :
[tex]\lambda = \dfrac{h}{\sqrt{2m(K.E)}}[/tex]
Putting all given values in above equation, we get :
[tex]\lambda = \dfrac{6.626\times 10^{-34}}{\sqrt{2\times 9.1\times 10^{-31}\times 3\times 10^6 \times 1.6\times 10^{-19}}}\\\\\\\lambda = 7.089 \times 10^{-13} \ m[/tex]
Hence, this is the required solution.
The pitch of a sound is most closely related to what ?
An object has an acceleration of 6.0 m/s/s. If the net force acting upon this object were tripled , then its new acceleration would be _____ m/s/s.
Answer:
18m/s/s
Explanation:
6 times 3= 18
Pick the correct word: inertia, whiplash, resistance, friction , force to fill up the blank in below question.
When hit from behind in a car crash, a passenger can suffer a neck injury from the forward and backward motion called _______.
Answer:
It is whiplash I hope this is right
A student presses her palm by her thumb with a force of 75 N . What would be the pressure under her thumb having contact area is 1.5 cm2
Step 1: Identify the knowns.
[tex] F=75 N [/tex]
[tex] A= 1.5 cm^2[/tex]
Step 2: Determine.
[tex] P= \frac {F} {A}\ [/tex]
[tex] P = \frac {75 N} {1.5 cm^2}\ = 50 Pa [/tex]
Answer:
50 Pascal
Explanation:
Pressure= Force/Area
P=75/1.5
=50 Pascal
MARK ME AS BRAINIEST IF MY ANSWER HELPED YOU :):)
A 0.05 kg ball is attached to the end of a 0.5 m long string. The ball is spun around a circle with a period of 0.20 s. What is the tension force in the string?
The ball spins once around the circle in 0.20 s, meaning it travels a distance equal to its circumference in that time, giving it a linear speed of
v = (2π (0.5 m)) / (0.20 s) = 5π m/s ≈ 15.708 m/s
Use this compute the magnitude of the centripetal acceleration a :
a = v²/ (0.5 m) = 50π² m/s² ≈ 493.48 m/s²
Use Newton's second law to compute the mangitude of the tension F in the string:
F = (0.05 kg) a = 5/2 π² N ≈ 24.674 N ≈ 25 N
True of False, in physics the term weight and force of gravity have the
same meaning?"
Help with both questions please.
Answer:
1) True
2) None of the above
Explanation:
Q # 1:
Weight is actually the gravitational force or force of gravity. So, it's true.
Q # 2:
None of above because force of gravity can not be negative. In order to have a negative weight, the body has to be "repelled" by gravity.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807What is the velocity of a wave with a frequency of 930 Hz and a wavelength of 0.50 m?
Answer:
Hi, thank you for posting your question here at Brainly.
To find the velocity of light or any electromagnetic wave, we use the equation: v = wavelength * frequency. Substituting,
v = 0.5 m * 930 1/s
v = 465 m/s
Brainiest please
Explanation:
Uncle Harry weighs 750 N. What is his mass in kg?
Answer:
W = MG
750 = M * 10
M = 750/10
M = 75 kg
Answer:
76.479 Kilograms Force (kgf)
Explanation:
Which of the following BEST describes Jupiter's seasons?
O A.
There are no significant seasonal changes.
B.
The seasons are much like Earth's.
OC.
The seasons are much shorter than Earth's.
OD. The seasons are much longer than Earth's.
Answer:
Jupiter does not have changing seasons like the Earth, but instead is believed to have a constantly stormy atmosphere. This is partly due to its tilt, which is only 3 degrees. The planet has a very turbulent atmosphere and is believed to have a lot of long-term storms.
So the answer is A : There are no significant seasonal changes.
Explanation:
Write true if the statement is correct and false if the statement
1. Magnetic poles always appear in pair.
2. Iron and nickel are examples of magnetic materials.
3. The two ends of a magnet are called magnetic poles.
4. Two similar magnetic poles attract each other
5. If one end of an iron bar attracts one pole of a com
Grade 7 Physics
then the iron bar must be a magnet.
Match the terms in column A with the phrases in colu
B
Answer:
true false
Explanation:
Answer:
1.true
2.true
3.true 4.false 5.true
Choose the sequence of energy forms that best fits each item.
Answer:
1. chemical energy --> electrical energy --> light energy
2. Electrical Energy --> Mechanical Energy
3. Electrical Energy --> Heat Energy
4. Chemical Energy --> Thermal Energy --> Mechanical Energy
5. Nuclear Energy --> Light energy and thermal energy
6. Mechanical Energy --> Electric Energy
7. Chemical Energy --> Electrical Energy --> Sound Energy
8. Mechanical Energy --> Sound Energy
Explanation:
1.FLASHLIGHT:
chemical energy --> electrical energy --> light energy
The chemical energy from the cell batteries is converted to electrical energy, which is used to produce the light energy in form of flashlight.
2.ELECTRIC SAW:
Electrical Energy --> Mechanical Energy
The electrical energy from the socket is converted to the mechanical energy used to run the saw blade.
3.TOASTER:
Electrical Energy --> Heat Energy
The electrical energy from the socket is converted to the heat energy (thermal energy) used in browning the bread.
4.GAS POWERED SCOOTER:
Chemical Energy --> Thermal Energy --> Mechanical Energy
The chemical energy from fuel, such as petrol is converted to heat (thermal energy) in the engine by the process of combustion. This heat is then used to do work by conversion into mechanical energy, through piston movement, which in turn moves the shaft and the scooter.
5.THE SUN:
Nuclear Energy --> Light energy and thermal energy
The nuclear reactions on Sun provide nuclear energy which is converted into light and thermal energy that reaches us on earth.
6.WIND TURBINE:
Mechanical Energy --> Electric Energy
The mechanical energy is provided by wind when it rotates the blade of turbine. This is then converted to electrical energy b the turbine.
7.IPOD:
Chemical Energy --> Electrical Energy --> Sound Energy
The chemical energy i supplied by the battery of ipod, which is converted to electrical energy and that electrical energy is used to produce sound by ipod.
8.SPEAKER VIBRATES
Mechanical Energy --> Sound Energy
The mechanical energy due to vibration produces sound energy.
Answer:
1. chemical energy --> electrical energy --> light energy
2. Electrical Energy --> Mechanical Energy
3. Electrical Energy --> Heat Energy
4. Chemical Energy --> Thermal Energy --> Mechanical Energy
5. Nuclear Energy --> Light energy and thermal energy
6. Mechanical Energy --> Electric Energy
7. Chemical Energy --> Electrical Energy --> Sound Energy
8. Mechanical Energy --> Sound Energy
Explanation:
A child's first bicycle has 12-inch tires. These tires have a 6-inch radius. How fa r does the bicycle move forward each time the wheel makes one complete rotation? Give your answer in meters. (1 inch = 0.022 meters) b. A woman's ten-speed bicycle has 27-inch tires (13.5-inch radius). How far does this bicycle …
Answer:
a. s = 0.96 m
b. s = 2.15 m
Explanation:
a.
The relationship between the linear displacement and the angular displacement is given as follows:
[tex]s = r\theta[/tex]
where,
s = linear distance covered = ?
r = radius of wheel = (6 in)(0.0254 m/1 in) = 0.1524 m
θ = angular displacement = (1 rev)(2π rad/1 rev) = 2π rad
Therefore,
[tex]s = (0.1524\ m) 2\pi[/tex]
s = 0.96 m
b.
Assuming, we have to find linear displacement here, as well:
[tex]s = r\theta[/tex]
where,
s = linear distance covered = ?
r = radius of wheel = (13.5 in)(0.0254 m/1 in) = 0.3429 m
θ = angular displacement = (1 rev)(2π rad/1 rev) = 2π rad
Therefore,
[tex]s = (0.3429 \ m) 2\pi[/tex]
s = 2.15 m
Name all of the steps on the Physical Activity Pyramid?
Answer:
The steps are:-
Moderate physical activityVigorous aerobicsVigorous sport and recreationMuscle fitness exerciseFlexibility exerciseAvoiding inactivityBalancing energyHow does an increase in thermal energy affect the temperature of each state of matter?
Answer:
Explanation:
When thermal energy is added to a substance, its temperature increases, which can change its state from solid to liquid (melting), liquid to gas (vaporization), or solid to gas (sublimation). ... When the pressure exerted on a substance increases, it can cause the substance to condense.
Answer:
Gases have the highest kinetic energy of any state of matter and thus occur at the highest temperatures. Increasing the temperature of a gas in an open system will not further change the state of matter because the gas molecules will only become infinitely further apart.
two Force one of 12 Newton and another 24 Newton acts at 90 degree with each other find the resultant of two force and its direction
Answer:
Fr = 26.83 [N]
Explanation:
To solve this problem we must use the Pythagorean theorem, since the forces are vector quantities, that is, they have magnitude and density. Therefore the Pythagorean theorem is suitable for the solution of this problem.
[tex]F_{r}=\sqrt{(12)^{2}+(24)^{2} } \\F_{r}=26.83[N][/tex]
How many kilometers in 487,320 meters? If there are 1,000 meters in one kilometer?
Answer:
48.732
Explanation:
Just move the denominator 3 times for the 0s in 1000.
A 10 Kg dog is running with a speed of 5.0 m/s what is the minimum work required to stop the dog
Answer:
25J
Explanation:
Given parameters:
Mass of the dog = 10kg
Speed of the dog = 5m/s
Unknown:
The minimum energy required to stop the dog = ?
Solution:
The dog is moving with a kinetic energy and to stop the dog, an equal amount of kinetic energy generated must be applied to the dog.
To find the kinetic energy;
K.E = [tex]\frac{1}{2}[/tex] m v²
m is the mass
v is the velocity
Now insert the parameters and solve;
K.E = [tex]\frac{1}{2}[/tex] x 10 x 5 = 25J
help please 10 pts and quick!
Answer:
A
Explanation:
WHICH ONE IS IT????
RINGS
POINT
GRAPH
READS
TALKS
Answer: c or b
Explanation:
If a net force of 375N is acting on a crate and there is 65N of friction
created, what is the magnitude net force the crate experiences?
375N
65N
310N
440N
Answer:
310 N
Explanation:
The net force, I assume, is an applied force that is causing motion of the crate. However, frictional force opposes this motion, so the frictional force is in the opposite direction. Overall, we can create a net force equation of this crate as
Fnet= Force applied + Force of friction
Thus,
Fnet= 375N -65N (because friction is in the opposite direction)
Then solve to get that the net force while the crate is in motion is 310N.
I WILL GIVE YOU BRAINLIEST!!
Which physical quantity does not change when a piece of copper is heated?
Answer:
Resistance, resistivity and drift velocity varies with relaxation time which is dependent on temperature.
Number of free electrons in a conductor remains invariant even if its temperature changes.Hence correct option is option D.
A thermal cap used in certain apparatus consist of silica rod which fits tightly inside an aluminium tube whose internal diameter is 8mm at 0 degree c … elcius.Calculate what change in temperature to produce channel whose cross section equal to 1 mm
Answer:
change in temperature is a decrease by 268.734 K
Explanation:
We are given;
Temperature: T1 = 0°C = 273 K
Internal diameter; d1 = 8mm
Final diameter; d2 = 1 mm
To solve this, we will use Charles law formula since pressure is constant.
Thus;
V1/T1 = V2/T2
Where T2 is the final temperature.
Now, V1 and V2 are volume
Volume is given by: V = area x height
We are told the cross section is equal except for the diameter.
Thus;
V1 = A1 × h
V2 = A2 × h
Thus;
(A1 × h)/T1 = (A2 × h)/T2
h will cancel out and making T2 the subject, we have;
T2 = (A2 × T1)/A1
A2 = π(d2)²/4
A1 = π(d1)²/4
Thus;
T2 = [(π(d2)²/4) × T1]/(π(d1)²/4)
π and 4 will cancel out to givw;
T2 = ((d2)²× T1)/(d1)²
T2 = (1² × 273)/8²
T2 = 273/64
T2 = 4.266 K
Thus;
Change in temperature = T2 - T1 = 4.266 - 273 = -268.734 K
Thus, change in temperature is a decrease by 268.734 K
b. The coefficient of friction between the tires and the road is 0.850 and the mass of the car is
1.35x10' kg. Draw the free body diagram of this situation and determine the applied force
that caused the acceleration from part a. (2 law: Fnet-ma)
Given:
u
בנו
Samt
g=9.8 m/s^2
am
(from part a)
Unknown:
Fapp = ?
Equation:
Fnet=ma
Fapp- umg=ma
Solution:
Answer:
156.26N
Explanation:
The data needed are incomplete. Let the acceleration of the body be 3.5m/s²
Other given parameters
Mass = 1.35×10^1 = 13.5kg
coefficient of friction between the tires and the road = 0.850
Acceleration due to gravity = 9.8m/s²
According to Newton's second law:
Fnet = ma
Fnet = Fapp - Ff
Fapp is the applied force
Ff is the frictional force = umg
The equation becomes:
Fapp - Ff = ma
Fapp-umg = ma
Fapp - 0.85(13.5)(9.8) = 13.5(3.5)
Fapp - 109.0125 = 47.25
Fapp = 47.25+109.0125
Fapp = 156.2625N
Hence the applied force that caused the acceleration is 156.26N
Note that the acceleration of the car was assumed. Any value of acceleration can be used for the calculation.
A ray of light incident in water strikes the surface separating water from air making an angle of 10 ° with the normal to the surface. (refractive index of water = 1.3) a) What is the angle of refraction? b) What should be the angle of incidence if we want an angle of refraction not greater than 45 ° ? c) What is the critical angle?
Answer:
a
[tex]\theta _2 = 13^o[/tex]
b
[tex]\theta _1 =32.94^o[/tex]
c
[tex]\theta_c = 53.05^o[/tex]
Explanation:
From the question we are told that
The angle of incidence is [tex]\theta_1 = 10^o[/tex]
The refractive index of water is [tex]n_1 = 1.3[/tex]
Generally Snell's law is mathematically represented as
[tex]n_1 sin(\theta_1) = n_2 sin(\theta_ 2)[/tex]
Here [tex]n_2[/tex] is the refractive index of air with value [tex]n_2 = 1[/tex]
[tex]\theta_2[/tex] is the angle of refraction
So
[tex]\theta _2 = sin^{-1}[\frac{n_1 * sin(\theta _1)}{n_2} ][/tex]
=> [tex]\theta _2 = sin^{-1}[\frac{1.3 * sin(10)}{1} ][/tex]
=> [tex]\theta _2 = 13^o[/tex]
Given that the angle should not be greater than [tex]\theta _2 =45^o[/tex] then the angle of incidence will be
[tex]\theta _1 = sin^{-1}[\frac{n_2 * sin(\theta _2)}{n_1} ][/tex]
=> [tex]\theta _1 = sin^{-1}[\frac{1 * sin(45)}{1.3} ][/tex]
=> [tex]\theta _1 =32.94^o[/tex]
Generally for critical angle is mathematically represented as
[tex]\theta_c = sin^{-1}[\frac{n_2}{n_1} ][/tex]
=> [tex]\theta_c = sin^{-1}[\frac{1}{1.3} ][/tex]
=> [tex]\theta_c = 53.05^o[/tex]
A gun recoils back when the bullet is fired ,why?
A gun recoils back when the bullet is fired due to conservation of momentum. Conservation of momentum suggest that - the net change of momentum in a closed system must be zero.
Therefore in equation form -
[tex]mv - mu = 0[/tex]
Why does a gun recoil when a bullet is fired?
Explanation:When a bullet is fired, the gun exerts a force on the bullet through the trigger (this is action) in a particular direction. According to Newton's Third Law, we know to every action there is an equal and opposite reaction; action and reaction act on different bodies. So, the bullet will also exert an equal and opposite reaction on the gun in the opposite direction. That is why a gun recoils when a bullet is fired from it.
Hope it helps.ray4918 here to helpwhat is this Regeneration
Answer:
Regeneration means that an organism regrows a lost part, so that the original function is restored.
A rocket is fired vertically upwards starting frkm rest. It accelerates at 30m/s for 4secs. At the end of 4secs it runs out of fuel but continues to rise. How long does it rise with reference to firing position?
Answer:
t = 16.5 s
Explanation:
First we apply first equation of motion to the accelerated motion of the rocket:
[tex]v_{f1} = v_{i1} + at_{1}[/tex]
where,
vf₁ = final speed of rocket during accelerated motion = ?
vi₁ = initial speed of rocket during accelerated motion = 0 m/s
a = acceleration of rocket during accelerated motion = 30 m/s²
t₁ = time taken during accelerated motion = 4 s
Therefore,
[tex]v_{f} = 0\ m/s + (30\ m/s^2)(4\ s)\\\\v_{f} = 120\ m/s[/tex]
Now, we analyze the motion rocket when engine turns off. So, the rocket is now in free fall motion. Applying 1st equation of motion:
[tex]v_{f2} = v_{i2} + g t_{2}[/tex]
where,
vf₂ = final speed of rocket after engine is off = 0 m/s
vi₂ = initial speed of rocket after engine is off = Vf₁ = 120 m/s
g = acceleration of rocket after engine is off = - 9.8 m/s² (negative sign for upward motion)
t₂ = time taken after engine is off = ?
Therefore,
[tex]0\ m/s = 120\ m/s + (- 9.8\ m/s^2)(t_{2})\\\\t_{2} = \frac{120\ m/s}{9.8\ m/s^2}\\\\t_{2} = 12.25\ s[/tex]
So, the time taken from the firing position till the stopping position is:
[tex]t = t_{1} + t_{2}\\\\t = 4 s + 12.5 s[/tex]
t = 16.5 s
HELP ASAPP!! WILL TRY TO GIVE BRAINLIEST
What is produced in the nucleolus?
Answer: Image result for What is produced in the nucleolus?
The nucleolus is a region found within the cell nucleus that is concerned with producing and assembling the cell's ribosomes. Following assembly, ribosomes are transported to the cell cytoplasm where they serve as the sites for protein synthesis.
Explanation: hope this helps! PLs mark me as brainliest! Thank you and have a wonderful day/night!
what other factor affected the gravitational force between the two objects in this simulation?
Answer:
The strength of the gravitational force between two objects depends on two factors, mass and distance. the force of gravity the masses exert on each other. If one of the masses is doubled, the force of gravity between the objects is doubled. increases, the force of gravity decreases
On an air track, a 4-kg cart moving at 3 m/s collides with a 2-kg cart that is
initially at rest. If the two carts stick together, what will be their velocity
after the collision? Show all calculations, including any equation(s) used,
and include correct measurement units. *
Your answer
Answer:
v₃ = 2 [m/s]
Explanation:
To solve such problems we must use the principle of conservation of momentum. That is, the linear momentum is conserved before and after the collision.
P = m*v
where:
P = linear momentum [kg*m/s]
m = mass [kg]
v = velocity [m/s]
The momentum is conserved before and after the collision, in this way we can obtain the following equation.
[tex](m_{1}*v_{1})+(m_{2}*v_{2})=(m_{1}+m_{2})*v_{3}[/tex]
where:
m₁ = mass of the cart moving = 4 [kg]
v₁ = velocity of the cart moving before the collision = 3 [m/s]
m₂ = mass of the cart initially at rest = 2 [kg]
v₂ = velocity of the cart at rest = 0
v₃ = velocity of the two carts combined (carts stick together) after the collision [m/s]
[tex](4*3)+(2*0)=(4+2)*v_{3}\\v_{3}=12/6\\v_{3}=2[m/s][/tex]
