A uniform plank $6$ m long and of mass $30$ kg rests on supports at its ends, A and B. A $60$ kg child stands $2$ m from A. Taking $g = 9.8$ m/s $^{2}$ , find the reaction at B.

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A particle has initial speed $5$ m/s and constant acceleration $2$ m/s $^{2}$ . How far does it travel in $6$ s?
A car travelling at $20$ m/s brakes uniformly to rest in $4$ s. How far does it travel while braking?
A stone is dropped from rest from a height of $45$ m. Taking $g = 9.8$ m/s $^{2}$ , what is its speed on reaching the ground?
A ball is thrown vertically upwards at $14.7$ m/s and returns to its starting height. Taking $g = 9.8$ m/s $^{2}$ , what is its time of flight?
A car of mass $1200$ kg has a driving force of $3000$ N and resistance of $600$ N. What is its acceleration?
Particles of mass $3$ kg and $5$ kg hang on either side of a smooth light pulley and are released from rest. Taking $g = 9.8$ m/s $^{2}$ , find…

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