Answer:
F = 12.5N
Explanation:
Force (F) = Mass (m) x Acceleration (a)
F = ma
F = (2.5kg) x (5m/s^2)
F = 12.5N
Answer:
mu = 0.56
Explanation:
The friction force is calculated by taking into account the deceleration of the car in 25m. This can be calculated by using the following formula:

v: final speed = 0m/s (the car stops)
v_o: initial speed in the interval of interest = 60km/h
= 60(1000m)/(3600s) = 16.66m/s
x: distance = 25m
BY doing a the subject of the formula and replace the values of v, v_o and x you obtain:

with this value of a you calculate the friction force that makes this deceleration over the car. By using the Newton second's Law you obtain:

Furthermore, you use the relation between the friction force and the friction coefficient:

hence, the friction coefficient is 0.56
Answer:

Explanation:
Height of the cliff is given as

now the time taken by the diver to hit the surface is given as



Now in the same time it has to cover a distance of 13.39 m
so the speed in horizontal direction is given as


