Answer:
21.8 m/s
Explanation:
At the top of the hill (crest), there are two forces acting on the motorcycle:
- The reaction force of the road, N (upward)
- The force of gravity, mg (downward)
Since the motorcycle is moving by circular motion, the resultant of these forces will give the centripetal force, so:

where the direction of the weight (mg) is equal to that of the centripetal force, and where
m is the mass of the cycle
g = 9.8 m/s^2 is the acceleration of gravity
v is the speed
r = 48.6 is the radius of the hill
The cycle loses contact with the road when the reaction force becomes zero:
N = 0
Substituting into the equation, we therefore find the maximum speed that is allowed for the cycle before losing constact:

Answer:
Tarzan, who weighs 688N, swings from a cliff at the end of a convenient vine that is 18m long. From the top of the cliff to the bottom of the swing he descends by 3.2m.
Explanation:
Force = mass x acceleration
Mass is given to be 250kg
Acceleration is given to be 5m/s^2
Force = 250kg x 5m/s^2 = 1,250 kgm/s^2 = 1,250 Newtons
Answer:
Explanation:
Diameter of pool = 12 m
radius of pool, r = 6 m
Total height raised, h = 3 + 2.5 = 5.5 m
density of water, d = 1000 kg/m³
Mass of water, m = Volume of water x density
m = πr²h x d
m = 3.14 x 6 x 6 x 5.5 x 1000
m = 113040 kg
Work = m x g x h
W = 113040 x 9.8 x 5.5
W = 6092856 J