Answer:
The reaction force is the force exerted by your body on the earth pulling upwards.
Explanation:
This can be explained using Newton's third law of motion which states that if object A exerts a force on object B, object B exerts a force of equal magnitude and opposite direction on object A. One characteristics of these force are that they act o 2 different bodies. In this example, the earth exerts a force on you. The Newton's reaction force would be you exerting a force of equal magnitude on the earth.
Answer: 600N
Explanation:
Centripetal force is the force that causes a body to move in a circular path.
Centripetal force = MV²/r
M = 75kg v = 80m/s r = 0.80km = 800m
Substituting the values given in the formula;
F = 75 × 80²/800
F = 600N
The magnitude of the resultant force on the 75kg pilot is 600N.
Question: A loader sack of total mass
is l000 grams falls down from
the floor of a lorry 200 cm high
Calculate the workdone by the
gravity of the load.
Answer:
19.6 Joules
Explanation:
Applying
W = mgh........................ Equation 1
Where W = Workdone by gravity on the load, m = mass of the loader sack, h = height, g = acceleration due to gravity
From the question,
Given: m = 1000 grams = (1000/1000) kilogram = 1 kg, h = 200 cm = 2 m
Constant: g = 9.8 m/s²
Substitute these values into equation 1
W = (1×2×9.8)
W = 19.6 Joules
Hence the work done by gravity on the load is 19.6 Joules