A barometer is used to measure air pressure!
Momentum would be the same before and after the collision
Before the collision:
Momentum of the single cart: 1 * 0.50 = 0.50
After the collision
velocity = 0.25m / s
1 * 0.25 + 1 * 0.25 =
0.25 * (1 + 1) =
0.25 * 2 =
0.50
Now new momentum will be 0.5
answer
the same before and after the collision
Answer:
Total number of lamps will be 4
Explanation:
We have given power of the lamp W = 400 watt
Potential difference across the lamp V=110 volt
We know that power is equal to 
So 

Total current is given 15 A
As it is given that lamps are connected in parallel so total current is the sum of current through each lamp
So number of lamp will be 
As the lamp can not be in negative
So total number of lamps will be 4
It would be option C. It rotates, or spins, on its axis, but it revolves around the sun.
Answer:
2.295 eV
Explanation:
maximum wavelength, λ = 542 nm = 542 x 10^-9 m
The work function of the metal is defined as the minimum amount of energy falling on the metal so that the photo electrons just ejects the surface of metal.

where, h is the Plank's constant and c be the speed of light
h = 6.634 x 10^-34 Js
c = 3 x 10^8 m/s


Wo = 2.295 eV
Thus, the work function of this metal is 2.295 eV.