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3 years ago

An object has a velocity of 8 m/s and a kinetic energy of 480 j. what is the mass of the object?

2 answers:

6 0

Hello!

We have the following data:

KE (Kinetic Energy) = 480 J
m (mass) = ? (in Kg)
v (speed) = 8 m/s

Formula to calculate kinetic energy:

 $KE = \frac{1}{2} *m*v^2$

Solving:

 $KE = \frac{1}{2} *m*v^2$

$480 = \frac{1}{2} *m*8^2$

$480 = \frac{1}{2} *m*64$

$480*2 = 64*m$

$960 = 64m$

$64m = 960$

$m = \frac{960}{64}$

$\boxed{\boxed{m = 15\:Kg}}\end{array}}\qquad\checkmark$

allochka39001 [22]3 years ago

3 0

KE=1/2*m*v^2
So 480=1/2 * m * 8^2
480=1/2 * m * 64
480=32 * m
480/32=m
15=m

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2 years ago

Two identical charges,2.0m apart,exert forces of magnitude 4.0 N on each other.What is the value of either charge?

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Answer:

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