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At the end of 3N force acts on the object during time interval of 1.5seconds with force acting towards right. A constant force of 4N to left
Question
At the end of 3N force acts on the object during time interval of 1.5seconds with force acting towards right. A constant force of 4N to left is applied for 3seconds. What is the velocity at the end of the 3seconds ?
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Physics
6 months
2021-08-10T14:36:10+00:00
2021-08-10T14:36:10+00:00 1 Answers
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Answers ( )
Answer:
v_f = -7.5 m / s
Explanation:
Let’s analyze this exercise a little, two forces that act on a body for different time intervals are indicated, each force creates an impulse and since this is a vector quantity we must add in the form of vectors. The net momentum is
we assume that the direction to the right is positive
I = I₁ + I₂
I = F₁ Δt₁ – F₂ Δt₂
I = 3 1.5 – 4 3
I = -7.5 N s
now let’s use the relationship between momentum and momentum, suppose the object starts from rest (vo = 0)
I = Δp
I = m (v_f – v₀)
v_f = I / m
v_f = -7.5 / m
to finish the calculation we must assume a mass m = 1 kg
v_f = -7.5 m / s
the negative sign in the body is moving to the left