Rain Man Problem — NEET Physics MCQs with Solutions
Free NEET Physics Rain Man Problem MCQs with step-by-step solutions (20 questions). Part of Motion in 2D. Practise online on Prepizo — no login needed.
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Questions with solutions
Q1 — Rain Man Problem · easy · numerical
Rain falls vertically at 4√3 ≈ 6.9 m/s. A man walks at 4 m/s. To keep himself dry he must tilt his umbrella forward from the vertical by an angle of:
A. 15°
B. 30° ✓ Correct
C. 45°
D. 60°
Solution: tanθ = v_man/v_rain = 4/4√3 = 1/√3 ⇒ θ = 30° from the vertical.
Q2 — Rain Man Problem · easy · numerical
Rain falls vertically at 16 m/s while a man runs horizontally at 12 m/s. The speed of the rain relative to the man is:
A. 28 m/s
B. 20 m/s ✓ Correct
C. 4 m/s
D. 16 m/s
Solution: v_rel = √(16² + 12²) = √(256 + 144) = √400 = 20 m/s.
Q3 — Rain Man Problem · easy · numerical
To a man walking at 6 m/s, vertically falling rain appears to make an angle of 30° with the vertical. The actual speed of the rain is:
A. 12 m/s
B. 3 m/s
C. 6√3 ≈ 10.4 m/s ✓ Correct
D. 2√3 ≈ 3.5 m/s
Solution: tan30° = v_man/v_rain ⇒ v_rain = 6/tan30° = 6√3 ≈ 10.4 m/s.
Q4 — Rain Man Problem · easy · numerical
Rain is falling vertically. To a walking man the rain appears to come at 8 m/s directed at 30° from the vertical. The speed of the man is:
A. 8 m/s
B. 4 m/s ✓ Correct
C. 16 m/s
D. 4√3 ≈ 6.9 m/s
Solution: The horizontal component of the apparent velocity equals the man's speed: v = 8 sin30° = 4 m/s.
Q5 — Rain Man Problem · easy · numerical
A car moves at 20 m/s while rain falls vertically at 20 m/s. The rain streaks on the car's side window make an angle with the vertical equal to:
A. 60°
B. 30°
C. 45° ✓ Correct
D. 90°
Solution: tanθ = v_car/v_rain = 20/20 = 1 ⇒ θ = 45°.
Q6 — Rain Man Problem · easy · numerical
Rain falls at 6 m/s making 30° with the vertical. The speed at which a man must walk (along the rain's horizontal drift) so that the rain appears vertical to him is:
A. 3 m/s ✓ Correct
B. 1.5 m/s
C. 6 m/s
D. 3√3 ≈ 5.2 m/s
Solution: He must match the horizontal component of the rain: v = 6 sin30° = 3 m/s.
Q7 — Rain Man Problem · easy · numerical
Rain falls at 12 m/s at 60° to the vertical. A man runs so that the rain appears to fall vertically on him. The apparent speed of the rain is:
A. 6 m/s ✓ Correct
B. 24 m/s
C. 6√3 ≈ 10.4 m/s
D. 12 m/s
Solution: Only the vertical component remains: v = 12 cos60° = 6 m/s.
Q8 — Rain Man Problem · easy · numerical
A cyclist rides at 10 km/h through rain falling vertically at 20 km/h. The rain appears to meet him at an angle from the vertical of:
A. 30°
B. 45°
C. tan⁻¹(1/2) ≈ 26.6° ✓ Correct
D. tan⁻¹(2) ≈ 63.4°
Solution: tanθ = v_cyclist/v_rain = 10/20 = 1/2 ⇒ θ = tan⁻¹(1/2) ≈ 26.6°.
Q9 — Rain Man Problem · easy · numerical
Rain falls vertically at 30 km/h while a scooterist travels at 40 km/h. The speed of the rain relative to the scooterist is:
A. 35 km/h
B. 70 km/h
C. 10 km/h
D. 50 km/h ✓ Correct
Solution: v_rel = √(30² + 40²) = √2500 = 50 km/h.
Q10 — Rain Man Problem · easy · numerical
To a man walking at 9 m/s, vertically falling rain appears inclined at 45° to the vertical. The actual speed of the rain is:
A. 9 m/s ✓ Correct
B. 9√2 ≈ 12.7 m/s
C. 9√3 ≈ 15.6 m/s
D. 4.5 m/s
Solution: tan45° = 9/v_rain = 1 ⇒ v_rain = 9 m/s.
Q11 — Rain Man Problem · easy · numerical
Rain falls vertically at 15 m/s. On the side window of a car moving at 15√3 ≈ 26 m/s, the rain streaks make an angle with the vertical of:
A. 60° ✓ Correct
B. 30°
C. 45°
D. 90°
Solution: tanθ = v_car/v_rain = 15√3/15 = √3 ⇒ θ = 60°.
Q12 — Rain Man Problem · easy · numerical
Rain falls vertically at 24 km/h. A cyclist rides at 10 km/h. The rain strikes the cyclist with a speed of:
A. 26 km/h ✓ Correct
B. 34 km/h
C. 24 km/h
D. 14 km/h
Solution: v_rel = √(24² + 10²) = √(576 + 100) = √676 = 26 km/h.
Q13 — Rain Man Problem · medium · numerical
When a man walks at 4 m/s the rain appears to fall vertically. When he speeds up to 8 m/s along the same line, the rain appears at 30° to the vertical. The vertical component of the rain's velocity is:
A. 4√3 ≈ 6.9 m/s ✓ Correct
B. 4/√3 ≈ 2.3 m/s
C. 4 m/s
D. 8 m/s
Solution: Vertical appearance at 4 m/s means the rain's horizontal component is 4 m/s; at 8 m/s the relative horizontal speed is 8 − 4 = 4 m/s, so tan30° = 4/v ⇒ v = 4√3 ≈ 6.9 m/s.
Q14 — Rain Man Problem · medium · numerical
Rain is falling vertically. A man walking at 7 m/s finds that the rain hits him at 30° to the vertical. The speed of the rain relative to him is:
A. 28 m/s
B. 14 m/s ✓ Correct
C. 3.5 m/s
D. 7√3 ≈ 12.1 m/s
Solution: The horizontal component of the relative velocity equals his speed: v_rel sin30° = 7 ⇒ v_rel = 14 m/s.
Q15 — Rain Man Problem · medium · numerical
Rain falls vertically at 10 m/s. A cyclist rides at such a speed that the rain meets him at 20 m/s. The speed of the cyclist is:
A. 10 m/s
B. 10√5 ≈ 22.4 m/s
C. 10√3 ≈ 17.3 m/s ✓ Correct
D. 30 m/s
Solution: v_cyclist = √(20² − 10²) = √300 = 10√3 ≈ 17.3 m/s.
Q16 — Rain Man Problem · medium · numerical
Rain falls at 16 m/s making 60° with the vertical. The speed at which a man must run so that the rain appears vertical to him is:
A. 8√3 ≈ 13.9 m/s ✓ Correct
B. 16 m/s
C. 4√3 ≈ 6.9 m/s
D. 8 m/s
Solution: He must cancel the horizontal component of the rain: v = 16 sin60° = 8√3 ≈ 13.9 m/s.
Q17 — Rain Man Problem · medium · numerical
Rain is falling vertically. When a girl walks at 1.5 m/s the rain appears to make 45° with the vertical. If she runs at 4.5 m/s in the same direction, the rain appears at an angle from the vertical of:
A. tan⁻¹(1/3) ≈ 18.4°
B. 45°
C. tan⁻¹(3) ≈ 71.6° ✓ Correct
D. 60°
Solution: From the 45° reading, v_rain = 1.5/tan45° = 1.5 m/s. Then tanθ = 4.5/1.5 = 3 ⇒ θ = tan⁻¹(3) ≈ 71.6°.
Q18 — Rain Man Problem · medium · numerical
A cyclist moving at 12 km/h finds vertically falling rain meeting him at 60° from the vertical. The actual speed of the rain is:
A. 24 km/h
B. 6 km/h
C. 4√3 ≈ 6.9 km/h ✓ Correct
D. 12√3 ≈ 20.8 km/h
Solution: tan60° = 12/v_rain ⇒ v_rain = 12/√3 = 4√3 ≈ 6.9 km/h.
Q19 — Rain Man Problem · medium · numerical
On the windscreen of a car moving at 40 km/h, vertically falling rain leaves streaks at 30° to the vertical. The speed of the rain is:
A. 40√3 ≈ 69.3 km/h ✓ Correct
B. 40/√3 ≈ 23.1 km/h
C. 20 km/h
D. 80 km/h
Solution: tan30° = v_car/v_rain ⇒ v_rain = 40/tan30° = 40√3 ≈ 69.3 km/h.
Q20 — Rain Man Problem · medium · numerical
Rain falls vertically at 6 m/s while a cyclist rides at 6√3 ≈ 10.4 m/s. The rain strikes the cyclist with a speed of:
A. 6√2 ≈ 8.5 m/s
B. 6 m/s
C. 12 m/s ✓ Correct
D. 6√3 ≈ 10.4 m/s
Solution: v_rel = √((6√3)² + 6²) = √(108 + 36) = √144 = 12 m/s.