Esther's tow rope exerts a steady 150 N net force on a stalled go-kart for 0.40 s.
How much impulse does the go-kart receive from the 150 N force over the 0.40 s?
You have seen the equation: J = FΔt.
Finding an impulse is a routine, and the same three steps work every time.
Step 1: write down the values in the question, and mark the unknown.
Step 2: write down the equation.
Step 3: substitute in the values, and calculate.
The result line always carries its unit: newton-seconds (N·s).
The F you substitute is the net force on the object, and Δt is the time that force acts.
Esther's tow rope exerts a steady 150 N net force on a go-kart for 0.40 s. Calculate the impulse delivered.
Write down the values:
F = 150 N, Δt = 0.40 s, J = ?
Write down the equation:
J = FΔt
Substitute in the values, and calculate:
J = 150 × 0.40 = 60
The go-kart receives an impulse of 60 N·s.
A batting machine's arm exerts a 200 N net force on a ball for 0.1 s. Calculate the impulse delivered.
Write down the values:
F = 200 N, Δt = 0.1 s, J = ?
Write down the equation:
J = FΔt
Substitute in the values, and calculate:
J = 200 × 0.1 = 20
The ball receives an impulse of 20 N·s.
A hockey stick exerts an 85 N net force on a puck for 0.02 s. Enter the impulse delivered in N·s.
A tennis racket exerts a 120 N net force on a ball for 0.035 s. Enter the impulse delivered in N·s.
Gunnar's wheelbarrow feels a 26 N net force for 2.5 s. Enter the impulse delivered in N·s.
A rowing stroke keeps a 90 N net force on a rowboat for 1.2 s. Enter the impulse delivered in N·s.
A soccer kick exerts a 950 N net force on the ball for 0.008 s. Enter the impulse delivered in N·s.
A tugboat's line provides a steady 4000 N net force on a small cargo boat for 15 s. Enter the impulse delivered in N·s.
A net force of 55 N acts on a sled for 0.60 s. Enter the impulse delivered in N·s.
One of Wilma's kayak strokes keeps a 70 N net force on the kayak for 0.9 s. Enter the impulse the stroke delivers in N·s.
A bumper car starts up from the line. While its motor runs at full power, the car feels a steady 36 N net force, and the run lasts 4.5 s. Enter the impulse delivered in N·s.