Question

(a) and (b) ??Thanks HELP d8 =1​

Answer 1

Explanation:

(a) You can solve this using kinematics or energy.

Using kinematics:

a = F/m = 90 N / 4 kg = 22.5 m/s²

v₀ = 0 m/s

Δx = 5 m

Find: v

v² = v₀² + 2aΔx

v² = (0 m/s)² + 2 (22.5 m/s²) (5 m)

v = 15 m/s

Using energy:

W = ΔKE

Fd = ½ mv²

(90 N) (5 m) = ½ (4 kg) v²

v = 15 m/s

(b) ΔU = mg Δh

ΔU = (4 kg) (9.8 m/s) (12 m sin 40° − 15 m)

ΔU = -290 J

W = ΔU = -290 J