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makvit [3.9K]
3 years ago
11

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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How much work is done if a 15 newton suitcase is lifted 2 m ?​
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The earth rotates once per day about an axis passing through the north and south poles, an axis that is perpendicular to the pla
Vladimir [108]

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given,

Radius of sphere = 6.38 × 10⁶ m

time  = 1 day = 86400 s

\omega = \dfrac{2\pi}{T}

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acceleration of the person

a = \omega^2R_E

a = (7.272 \times 10^{-5})^2(6.38 \times 10^6)

a = 0.03374 m/s^2

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R = R_E cos \theta

R = 6.38 \times 10^6\times cos 61^0

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v = R \omega

v = 3.093 \times 10^6 \times 7.272 \times 10^{-5}

v = 225 m/s

acceleration of the person

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4 0
3 years ago
In the absence of a gravitational field, you could determine the mass of an object (of unknown composition) by:
lina2011 [118]

Answer:

A) By applying a known force, and measuring it's acceleration.

Explanation:

This is actually something that astronauts do in space as a mathmatical exercise when calculating the mass of an object since F = m × a.

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3 0
3 years ago
A car is being tested for safety by colliding it with a brick wall.The 1300 kg car is initially driving towards the wall at a sp
serg [7]

Answer:

44200 N

Explanation:

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.

Replacing t = 0.5s, m = 1300 kg, vf = -2 m/s, and vi = 15 m/s and solving for F, we get

\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
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