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3 years ago

Will mark brainliest! Please help!

Physics

1 answer:

djverab [1.8K]3 years ago

3 0

Answer:

30 seconds

Explanation:

A = A02^-(t/hl)

--> ln(A/A0) = -(t/hl)ln2

solving for hl,

hl = -t x ln2 /ln(A/A0)

= -(60 min)xln2/ln(50/200)

= 0.5 min or 30 seconds

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4 0

3 years ago

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3 years ago

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Answer:

44200 N

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To calculate the average force exerted on the car, we will use the following equation

$\begin{gathered} Ft=\Delta p \\ Ft=m(v_f-v_i) \end{gathered}$

Where F is the average force, t is the time, m is the mass, vf is the final velocity and vi is the initial velocity of the car.

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$\begin{gathered} F(0.5s)=(1300\text{ kg\rparen\lparen-2 m/s - 15 m/s\rparen} \\ F(0.5s)=(1300\text{ kg\rparen\lparen-17 m/s\rparen} \\ F(0.5s)=-22100\text{ kg m/s} \\ F=\frac{-22100\text{ kg m/s}}{0.5\text{ s}} \\ F=-44200\text{ N} \end{gathered}$

Therefore, the average force exerted on the car by the wall was 44200 N

4 0

1 year ago