Please answer both if possible 1.) A spring with spring constant k hangs vertica
ID: 1644758 • Letter: P
Question
Please answer both if possible
1.) A spring with spring constant k hangs vertically. Fermina hangs a mass from the spring and displaces it from its equilibrium position so that it oscillates up and down at a frequency f. She then removes this mass and replaces it with a mass with four times the mass of the original one, and sets it to oscillate again. What will the frequency be now?
A. 2 f
B. f
C. f/4
D. f/2
2.) What causes the restoring force for a simple pendulum?
A. tension
B. gravity
C. normal force
D. air resistance
Explanation / Answer
1) angular frequency is given by f= 1/2(pi)sqrt(k/m)
therefore, frequency of oscillation is inversely proportional to square root of mass
when the mass is replaced by four times the mass, the frequency will become f/sqrt(4) = f/2
therefore, correct option is D
2)restoring for is the force that tries to bring back the displaced pendulum bob back to its equilibrium position. For, pendulum it is the weight , i.e., gravity force which is the restoring force
correct option is B