Hello everyone, i'm new to this forum. I am kinda having trouble with a physics problem. Could someone please help me out with 3 problems. Thanks.(adsbygoogle = window.adsbygoogle || []).push({});

A rocket is fired vertically with an upward acceleration of 27 m/s2. After 21 s, the engine shuts off and the rocket continues as a free particle until it reaches the ground.

(a) What is the highest point the rocket reaches?

km

(b) What is the total time the rocket is in the air?

s

(c) What is the speed of the rocket just before it hits the ground?

m/s

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Two stones are dropped from the edge of a 200-m cliff, the second stone 1.3 s after the first.

(a) How long after the second stone is dropped will the separation between the two stones be 35 m?

s

(b) At this point, how far below the clifftop is the second stone?

m

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A particle undergoes three successive displacements in a plane, as follows: 2.0 m southwest, 5.0 m east, and 8.0 m in a direction 60.0° north of east. Choose the y axis pointing north and the x axis pointing east.

(a) Find the components of the first displacement.

m east and m north

Find the components of the second displacement.

m east and m north

Find the components of the third displacement.

m east and m north

(b) Find the components of the resultant displacement.

m east and m north

(c) Find the magnitude and direction of the resultant displacement.

m at an angle of ° North of East

(d) Find the displacement that would be required to bring the particle back to the starting point.

m i + m j.

I got some fromt the last one correct but am having trouble with the whole concept.

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# Homework Help: First Post. Kinematics

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