Answer:
2560J
Explanation:
By definition the kinetic energy can be calculated in the following way:
K = (mv²)/2 = 80kg·(8.0m/s)²/2 = 2560 J
Answer: The answer is B
Explanation: It is staying in a steady speed position
Answer:D
Explanation:according to the law of conservation of energy/momentum, when two bodies collides, their total momentum and energy before and after collision are equal. Given that the two bodies move with the same velocities after collision, means that the law has not been violated since momentum = mass x velocity (where mass is constant)
Answer:
If the particle is an electron 
If the particle is a proton, 
Explanation:
Initial speed at the origin, 
to +ve x-axis
The particle crosses the x-axis at , x = 1.5 cm = 0.015 m
The particle can either be an electron or a proton:
Mass of an electron, 
Mass of a proton, 
The electric field intensity along the positive y axis
, can be given by the formula:

If the particle is an electron:



If the particle is a proton:


