What is the centripetal force that would be required to keep a 4.0 kg mass moving in a horizontal circle with a radius of 0.80 m
2 answers:
Answer:
D. 1.8 × 102 newtons radially inward
Explanation:
The magnitude of the centripetal force is given by:
where
m is the mass of the object
v is the tangential speed
r is the radius of the circular trajector
In this problem, we have m = 4.0 kg, v = 6.0 m/s and r = 0.80 m, therefore substituting into the equation we get
The centripetal force is the force that keeps the object in a circular trajectory, so it is a force that is always directed inward (towards the centre of the circular path) and radially. Therefore, the correct answer is
D. 1.8 × 102 newtons radially inward
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