figure 2.1 above shows a velocity-time
graph for a motorcycle travelling in a straight line. calculate and
(i) the instantaneous acceleration at t= 2 s and t = 12 s
(ii) the average acceleration for the time
interval between t=5 s and t = 20 s

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )

Debris produced by mining is called

Aturntable that spins at a constant 74.0 rpm takes 3.10 s to reach this angular speed after it is turned on. find its angular acceleration (in rad/s2), assuming it to be constant, and the number of degrees it turns through while speeding up.