A mass–spring system is driven simultaneously by two external forces of equal…

PHYSICS · Single correct · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics

Problem

A mass–spring system is driven simultaneously by two external forces of equal amplitude

F_0

and the same frequency

\omega

, both acting in phase. Compared with the steady-state amplitude produced when only one force

F_0\cos \omega t

acts, the steady-state amplitude when both forces act together is (a)

A

remains unchanged (b)

A

increases by a factor

\sqrt{2}

(c)

A

is doubled (d)

A

becomes four times as large