For standing car, v=μT=μMg
For accelerating car,
υ′=μ(Mg)2+(Ma)2
⇒6060.5=Mg(Mg)2+(Ma)2
⇒(1+1201)2=Mg(Mg)2+(Ma)2
⇒1+1202=1+g2a2
≈1202=21g2a2
∴a=g1204=30g≈5g
A heavy ball of mass M is suspended from the ceiling of a car by a light string of mass m (mll M). When the car is at rest, the speed of transverse…
JEE Main 2019 — Physics Mechanics
2019mcqmedium
A heavy ball of mass M is suspended from the ceiling of a car by a light string of mass m(m≪M). When the car is at rest, the speed of transverse waves in the string is 60ms−1. When the car has acceleration a, the wave-speed increases to 60.5ms−1. The value of a, in terms of gravitational acceleration g, is closed to
Official previous-year question
Held on 9 Jan 2019 · Verified 6 Jul 2026.
Options
- A
10g
- B
20g
- C
5g
- D
30g
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