Answer:
option (b) 4900 N
Explanation:
m = 2000 kg, R = 6380 km = 6380 x 10^3 m, Me = 5.98 x 10^24 kg, h = R
F = G Me x m / (R + h)^2
F = G Me x m / 2R^2
F = 6.67 x 10^-11 x 5.98 x 10^24 x 2000 / (2 x 6380 x 10^3)^2
F = 4900 N
Answer:
μ = 0.375
Explanation:
F = Applied force on the trash can = 75 N
W = weight of the trash can = 200 N
f = frictional force acting on trash can
Since the trash can moves at constant speed, force equation for the motion of can is given as
F - f = 0
75 - f = 0
f = 75 N
μ = Coefficient of friction
frictional force is given as
f = μ W
75 = μ (200)
μ = 0.375
Answer:

Explanation:
According to the free body diagram, in this case, we have:

Recall that the force of friction is given by:

Replacing and solving for the coefficient of kinetic friction:

We have an uniformly accelerated motion. Thus, the acceleration is defined as:

Finally, we calculate
:

Answer:
The potential energy of the hiker is
.
Explanation:
Given that,
Mass of the hiker, m = 61 kg
Height above sea level, h = 1900 m
We need to find the potential energy associated with a 61-kg hiker atop New Hampshire's Mount Washington. The potential energy is given by :

g is the acceleration due to gravity

So, the potential energy of the hiker is
. Hence, this is the required solution.