Answer:
a. Potential energy decreases and Kinetic energy increases
Explanation:
Because as he comes down due to its steepness the speed of the boy or you can say his KE increases and since he comes from a high position (hill) to the lower ground his potential energy decreases simultaneously
Answer:
B. +5.75 m/s
Explanation:
When there are two bodies, a and b, whose velocities measured by a third observer (in this case, the ground) are
and
respectively, the relative velocity of B with respect to A is given by:

Thus, the velocity of the girl relative to the lawnmower is:

Answer:
6360 km
Explanation:
Use the kinematics equation
. We are given t = 7.95 hours and a = 0 m/s^2 (constant speed means there is no acceleration). Solve for x.

OoooooooooOoOoOoOoOoOoOOoOooof
a)
for the puck :
F = force applied in the direction of pull
N = normal force on the puck in upward direction by the surface of table
W = weight of the puck in down direction due to force of gravity
b)
along the vertical direction , normal force balance the weight of the puck , hence the net force is same as the force of pull F .
so F = ma where m = mass of puck , a = acceleration
Fnet = F
c)
since the net force acts in the direction of force of pull F , hence the puck accelerates in the same direction .