The figure shows a 100-kg block being released from rest from a height of 1.0 m.
ID: 1618487 • Letter: T
Question
The figure shows a 100-kg block being released from rest from a height of 1.0 m. It then takes it 0.71 s to reach the floor. What is the mass m of the other block? The pulley has no appreciable mass or friction. A) 60 kg B) 54 kg C) 48 kg D) 42 kg E) 30 kg An object of mass 10.0 kg is attached to an ideal massless spring and allowed to hang in the Earth's to gravitational field. The spring stretches 3.0cm before it reaches its equilibrium position. If this system is allowed oscillate, what will be its frequency? A) 2.6 Hz B) 2.23 Hz C) 2.03 Hz D) 2.88 Hz E) 3.52 Hz The position of an object as a function of time is given by s = bt^2, where b = 2.0 m/s and c = 67 m/s and s and t are in SI units. What is the instantaneous velocity of the object when 2.525 s? A) 1.7 ms B) 2.1 m/s C) 2.3 m/s D) 2.7 m/s E) 3.4 m/sExplanation / Answer
16) I = constant
=> (2.25)(6.88) = (1.8)(final)
=> final = 8.6 rad/s
option (B) is the correct answer
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17) G = 6.67*10-11 Nm2/kg2
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18) s = ut + (1/2)at2
=> 1 = (1/2)a(0.712)
=> a = 3.97 m/s2
(100g) - T = (100a)
=> T = 100(g-a)
=> T = 584.25
T - mg = ma
=> m = T/(g+a)
=> m = 42.4 kg
option (D) is the correct answer
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19) k = mg/x = 3270
T = 2(m/k) = 0.348
f = 1/T = 2.88 Hz
option (D) is the correct answer
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20) s = bt2 - ct
=> ds/dt = 2bt - c
=> v = 2bt - c
At t = 2.525s,
v = (2*2*2.525) - 6.7
=> v = 3.4 m/s
option (E) is the correct answer