Answer:
Potential difference though which the electron was accelerated is 
Explanation:
Given :
De Broglie wavelength , 
Plank's constant , 
Charge of electron , 
Mass of electron , m=9.11\times 10^{-31}\ kg.
We know , according to de broglie equation :

Now , we know potential energy applied on electron will be equal to its kinetic energy .
Therefore ,

Putting all values in above equation we get ,

Hence , this is the required solution.
Answer:
The classification of that same issue in question is characterized below.
Explanation:
The given values are:
Current, I = 50.0 A
Diameter, d = 0.10 cm
(a)...
As we know,
⇒ Magnetic force = Copper wire's weight
So,
⇒ 
On putting the estimated values, we get
⇒ 
⇒ 
⇒ 
(b)...
As we know,
⇒ 
⇒ 
⇒ 
⇒
Answer:
b) It is impossible to tell without knowing the masses.
Explanation:
The temperature change of a substance when it receives/gives off a certain amount of heat Q is given by

where
Q is the amount of heat
m is the mass of the substance
Cs is the specific heat capacity of the substance
In this case, we have a hot piece of aluminum in contact with a cold piece of copper: the amount of heat given off by the aluminum is equal to the amount of heat absorbed by the copper, so Q is the same for the two substances. However, we see that the temperature change of the two substances depends on two other factors: the mass, m, and the specific heat, Cs. So, since we know only the specific heat of the two substances, but not their mass, we can't tell which object will experience the greater temperature change.
Answer:
No, i disagree.
Explanation:
If the car is moving, it only has a velocity with a component in the horizontal direction. If we use galilean relativity, the velocity of the ball observed by my friend standing in the ground should only be affected in the horizonal direction, while the vertical stays the same for both observers.
efficiency= [useful energy transferred ÷ total energy supply]×100%
So, [5500÷10000]×100%=0.55×100
=55%