The trajectory shows the path of a ball kicked. The ball's position is shown at 1s interval until t=3. At t=1, the ball's velocity is V= (2i +2j)m/s. What is the ball's velocity at t=0s and at t=3s? What was the ball's launch angle?

Question

The trajectory shows the path of a ball kicked. The ball's position is shown at 1s interval until t=3. At t=1,   the ball's velocity is V= (2i +2j)m/s. What is the ball's velocity at t=0s and at t=3s? What was the ball's launch angle?

potatoes.ramu · Answer

Isn't the velocity of the ball at t=0s, zero?

potatoes.ramu · Answer

Magnitude of the velocity at t=1, is $$\sqrt{8}$$

anonymous · Answer

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anonymous · Answer

Yes, that is at 1 second, how about at 0 seconds,the initial vertical velocity

potatoes.ramu · Answer

at 0 seconds, won't the velocity be zero? The ball starts from rest... so the initial velocity at t=0 will be zero.

anonymous · Answer

how do we calculate the vertical component of vector v at t=0, that is the question here I think. the horizontal component is 2i, it will not change.

potatoes.ramu · Answer

Use sin90 to find vertical component

anonymous · Answer

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