Question:
A 0.5 kg object is initially at rest on a frictionless surface. Suddenly, a constant force of 10 N is applied to the object.
a) Calculate the impulse experienced by the object over a time interval of 2 seconds.
b) Calculate the final velocity of the object after the force is applied.
c) Calculate the momentum of the object after the force is applied.
Answer:
a) To calculate the impulse experienced by the object, we can use the equation:
Impulse (J) = Force (F) × time interval (Δt)
Given:
Force (F) = 10 N
Time interval (Δt) = 2 s
Substituting the given values into the equation:
Impulse (J) = 10 N × 2 s = 20 N·s
Therefore, the impulse experienced by the object over a time interval of 2 seconds is 20 N·s.
b) To calculate the final velocity of the object, we can use the equation:
Impulse (J) = Change in momentum (Δp)
The impulse is equal to the change in momentum of the object. Using the equation:
Δp = m × Δv
Where: Δp = change in momentum m = mass of the object Δv = change in velocity
Since the object is initially at rest, the initial velocity (u) is 0. Therefore, we have:
Δv = v - u = v - 0 = v
Rearranging the equation:
Δp = m × Δv 20 N·s = 0.5 kg × Δv
Solving for Δv:
Δv = 20 N· s / 0.5 kg = 40 m/s
Therefore, the final velocity of the object after the force is applied is 40 m/s.
c) Momentum (p) is defined as the product of an object's mass and its velocity. So, we can calculate the momentum using the equation:
p = m × v
Given:
Mass (m) = 0.5 kg Velocity (v) = 40 m/s
Substituting the given values into the equation:
p = 0.5 kg × 40 m/s = 20 kg·m/s
Therefore, the momentum of the object after the force is applied is 20 kg·m/s.