A body travels 30m in 5s, 45m in 7s and then 65m in the last 5s. Find the average speed of the body

1 answer:

8 0

We can find the average speed of the body by finding the total distance covered, and then dividing it by the total time of the motion.

The total distance covered is:
$S=30 m + 45m+65m=140 m$

while the total time of the motion is
$t=5 s+7s+5 s=17 s$

So, the average speed of the body is:
$v= \frac{S}{t}= \frac{140 m}{17 s}=8.24 m/s$

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a skydiver jumps out of a plane. describe how gravitational potential energy changes as the skydiver falls. describe how the sky

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A mass of 5kg starts from rest and pulls down vertically on a string wound around a disk-shaped, massive pulley. The mass of the

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Answer:

c. V = 2 m/s

Explanation:

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$E_i =E_f$

so:

Mgh = $\frac{1}{2}IW^2 +\frac{1}{2}MV^2$

where M is the mass, g the gravity, h the altitude, I the moment of inertia of the pulley, W the angular velocity of the pulley and V the velocity of the mass.

Also we know that:

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Also, the moment of inertia of the disk is equal to:

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