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High-speed photos of a 220-ug flea jumping vertically show that the jump lasts 1.2 ms and involves an average vertical acceleration of 100g. What (a) average force and (b) impulse does the ground exert on the flea during its jump? (c) What's the change in the flea's momentum during its jump?

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Final answer:

a) The average force exerted by the ground on the flea during its jump is 5.88 × 10⁻⁴ N. b) The impulse exerted by the ground on the flea during its jump is 7.06 × 10⁻⁷ Ns. c) There is no change in the flea's momentum during its jump.

Step-by-step explanation:

Given:

Mass of flea (m) = 6.00 × 10⁻⁷ kg

Jump duration (t) = 1.2 ms = 1.2 × 10⁻³ s

Average vertical acceleration (a) = 100g

To find:

(a) Average force exerted by the ground on the flea

(b) Impulse exerted by the ground on the flea

(c) Change in the flea's momentum during the jump

(a) Average force (F) can be calculated using Newton's second law:

F = ma

F = (6.00 × 10⁻⁷ kg)(100g)×(9.8 m/s²)

F = 5.88 × 10⁻⁴ N

(b) Impulse (I) can be calculated using the formula:

I = Ft

I = (5.88 × 10⁻⁴ N)(1.2 × 10⁻³ s)

I = 7.06 × 10⁻⁷Ns

(c) Change in momentum (Δp) can be calculated using the formula:

Δp = mΔv

Since the flea jumps vertically and comes to a stop, the change in velocity (Δv) will be equal to the final velocity (v_f) of 0 m/s.

Δp = (6.00 × 10⁻⁷ kg)(0 m/s - 0 m/s) = 0

Therefore, the answers to the questions are:

(a) The average force exerted by the ground on the flea during its jump is 5.88 × 10⁻⁴ N.

(b) The impulse exerted by the ground on the flea during its jump is 7.06 × 10⁻⁷ Ns.

(c) There is no change in the flea's momentum during its jump, as the final momentum is equal to the initial momentum of 0 kgm/s.

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