Answer:
D
Explanation:
D) The overall work done by gravity is zero
This statement is correct .
If m be the mass of each of the children and h be the height of tower
work done by gravity on the boys in going up = - mgh
it is so because force applied by gravity = mg downwards and displacement
is upwards
work done will be negative = - mgh
Work done by gravity on boys when they come down = + mgh because both force and displacement are downwards .
Hence total work done = - mgh + mgh = 0.
The children will have same kinetic energy as the inclined surface is friction-less so no energy will be dissipated hence addition of energy to boys in both the cases will be same.
Answer:
When you lift the ball, you are doing work to increase its gravitational potential energy. When you then release the ball, gravitational energy is transformed into kinetic energy as the ball falls. When the ball hits the floor, the ball's shape changes as it flattens against the floor.
Explanation:thats should be the way^^ in explaining
Acceleration, a = (v - u)/t
where v is the final velocity, u is the initial velocity, and t is the time.
This formula on a velocity time graph represents the slope of the graph.
Answer:
Force exerted by car on truck will be 6000 N in opposite direction
Explanation:
It is given that mass of the car is one quarter of the mass of the truck
Force exerted by the truck on the car is 6000 N
We have to find the force exerted by car on the truck
According to newtons third law for any action there is equal and opposite reaction
So force exerted by car on the truck will be equal to 6000 N in opposite direction
Answer:
The velocity of the proton is 
Explanation:
The momentum of a particle is defined as the product of its mass by its velocity and we can calculate it using the following formula:
p=m*v Equation (1)
Where:
p: Is the momentum in kg*m/s
m: Is mass of the particle in kg
v: Is the velocity of the particle in m/s
Data known:
m= 1,6726 × 10^–27 kg : mass of the proton
p= 4.96 X 10^-19 kg.m/s.
We replace this data in the Equation (1):




Answer: The velocity of the proton is 