3. If a spring extends by 3 cm when a 4 N weight is suspended from it, find the extension when the weight is changed to
(a) 8 N
(b) 10 N
(c) 14 N

Keneila is attempting to ski down a 20 m high friction free hill for the first time. she has a speed 10 m/s at the top. what is her kinetic energy when she is a the bottom, 20 m ? (a)2500 j (b)9800 j (c)12300 j (d)3100j (e)15000j

Aclarinetist, setting out for a performance, grabs his 3.350 kg clarinet case (including the clarinet) from the top of the piano and carries it through the air with an upward force of 24.65 n. find the case's vertical acceleration. indicate an upward acceleration as positive and a downward one as negative.

Efficiency is the ratio of to for a system a)power in to power in b)power in to power out c) power out to power out d) power out to power in