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10 votes
Please help really desperate as it is due in a couple of hours.

A cricket ball is hit from a point A with velocity of (pi + qj)ms-1 at an angle theta above the
horizontal, i and j are the unit vectors horizontally and vertically upwards respectively. The point
A is 0.8 m vertically above the point 0, which is on horizontal ground.
The ball takes 4 seconds to travel from A to B, where B is on the ground and OB = 64 m, as
shown in the diagram. By modelling the motion of the ball as that of a particle moving freely under gravity,
a) find the value of p and the value of q

b) find the initial speed of the ball

c) find the exact value of tan theta

d )find the length of time for which the cricket ball is at least 5 m above the ground.

e )State an additional physical factor which may be taken into account in a refinement of the above model to make it more realistic.​​

User Harini
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5.2k points

1 Answer

9 votes
the answer is b, fine the initial speed of the ball
User Alex Quinto
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5.3k points