Two springs of constants K₁=200 N m⁻¹ and K₂=160 N m⁻¹ are attached to a 10 kg block. Initially the block is at equilibrium and both springs are unstretched. At t=0 an impulse of 50 N s is given.

Question

G1 Physics · Accepted Answer

Impulse J=50 N s gives initial speed v₀=J/m=5 m s⁻¹, so B is true. The two springs oppose displacement and add: kₑ=200+160=360 N m⁻¹. Thus ω=√(360/10)=6 rad s⁻¹, period T=2π/6=π/3 s, so A is true. Amplitude A=v₀/ω=5/6≈0.833 m, so D is false and C is false. Correct answers: A, B.