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skelet666 [1.2K]
3 years ago
11

Objects fall near the surface of the earth with a constant downward acceleration of 10 m/s2 . At a certain instant an object is

moving upward at 20 m/s. What is its velocity 2 sec later?
Physics
1 answer:
anastassius [24]3 years ago
6 0

Answer:

After 2 seconds the velocity of the object is 0 m/s.

Explanation:

The velocity at 2 seconds later can be calculated as follows:

V_{f} = V_{0} - gt

Where:

V_{f}: is the velocity at 2 seconds

V_{0}: is the initial velocity = 20 m/s

g: is the gravity = 10 m/s²

t: is the time = 2 s

Hence, the final velocity is:

V_{f} = V_{0} - gt = 20 m/s - 10 m/s^{2}*2 s = 0 m/s

This value (0 m/s) means that the object has reached the maximum height.

Therefore, after 2 seconds the velocity of the object is 0 m/s.

I hope it helps you!

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Let's start with the part without rubbing, let's find the speed that the box reaches., For this we use the conservation of mechanical energy in two points: maximum compression and when the box is free (spring without compression)

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Let's reduce the SI units measures

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Take the ratio of the two fields energy density

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