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3 years ago

8

6. A car accelerates from rest to 5m/s in 20 s. The force from the engine is 2000N. The force of air resistance and friction act

ing is 1000N. What is the cars mass?

1 answer:

otez555 [7]3 years ago

4 0

Answer:

net force= 2000-1000=1000

a=v-u/t=5/20=1/4

m=?

m=f/a

=1000÷1/4=4000kg

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How much power does it take to lift 70.0 N to 5.0 m high in 5.00 s?

lesantik [10]

Answer:

Power = 70 W

Explanation:

Given that,

Force, F = 70 N

Height, h = 5 m

Time, t = 5 s

We need to find the power of the object. We know that,

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Put all the values,

$P=\dfrac{Fd}{t}\\\\P=\dfrac{70\times 5}{5}\\\\P=70\ W$

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2 years ago

A busy chipmunk runs back and forth along a straight line of acorns that has been set out between his burrow and a nearby tree.

saveliy_v [14]

Answer: a = 1.32m/s2

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3 years ago

A girl weighing 50 kgf wears sandals of pencil heel of area of cross section 1 cm^2, stands on the floor.An elephant weighing 20

Klio2033 [76]

Answer:

$\boxed{{\boxed{\blue{ 12.5}}}}$

Explanation:

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Area of both heels;

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Now;

$\rm = \dfrac{Pressure \: Exerted \: by \: the \: Girl}{Pressure \: exerted \: by \: the \: elephant}$

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Thus, the girl's pointed heel sandals exert 12.5 times more pressure P than the pressure P exerted by the elephant.

I aspire this helps!

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2 years ago

An object falls from the top of a building that is 25 m high. Air resistance is negligible.

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The velocity of the object s calculated as 22.1 m/s.

<h3>What is the speed of the object?</h3>

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