On a flat surface a moving bicycle has more kinetic energy than a stationary car
Answer:
just before landing the ground
Explanation:
Let the velocity of projection is u and the angle of projection is 30°.
Let T is the time of flight and R is the horizontal distance traveled. As there is no force acting in horizontal direction, so the horizontal velocity remains constant. Let the particle hits the ground with velocity v.
initial horizontal component of velocity, ux = u Cos 30
initial vertical component of velocity, uy = u Sin 30
Time of flight is given by

Final horizontal component of velocity, vx = ux = u Cos 30
Let vy is teh final vertical component of velocity.
Use first equation of motion
vy = uy - gT


vy = - u Sin 30
The magnitude of final velocity is given by


v = u
Thus, the velocity is same as it just reaches the ground.
Answer:
Explanation:The work done is twice as great for block B because it is moved twice the ... Equal forces are used to move blocks A and B across the floor. ... Does the normal force of the floor pushing upward on the block do any work? ... Suppose that the mass is halfway between one of the extreme points of its motion and the center point.
I think it is D a light bulb