Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Advanced2019PhysicsLaws of MotionActual

A block of weight 100 N is suspended by copper and steel wires of same cross-sectional area 0.5 c m 2 and, length 3 m and 1 m , respectively. Their other ends are fixed on a ceiling as shown in figure. The angles subtended by copper and steel wires with ceiling are 30 o and 60 o , respectively. If elongation in copper wire is Δ l C and elongation in steel wire is Δ l S , then the ratio Δ l C Δ l S is _____. [Young's

Correct answer

0

Step-by-step solution

2.00 Resolving in components ⇒ ∑ F x = 0 ⇒ T S c o s 60 = T C ⋅ c o s 30 ⇒ T S ⋅ 1 2 = T C ⋅ 3 2 ⇒ T S = 3 ⋅ T C Δ l C Δ l S = T C ⋅ l C T S ⋅ l S Y S ⇒ Δ l C Δ l S = T C T S l C l S Y S Y C = 1 3 3 1 2 × 10 11 1 × 10 11 = 2

Practice Laws of Motion on Quantrex Academy →

More from Laws of Motion

A block takes t time to slide down a plane inclined at 45° to the horizontal. If the surface is made smooth (frictionless), the block takes time t 2 to slide down the plane. The co 2026Two blocks ( P and Q ) with respectively masses 2 kg and 1.5 kg are joined by a massless thread. These blocks are mounted on a frictionless pulley which is fixed on the edge of a c 2026A mass of 1 kg is kept on an inclined plane with 30° inclination with respect to horizontal plane and it is at rest initially. Then the whole assembly is moved up with constant vel 2026Three masses m₁ = 4 kg, m₂ = 4 kg and m₃ = 6 kg are suspended from a fixed smooth frictionless pulley as shown in the figure below. The value of T₁/T₂ is _____. (take g = 10 m/s ^2 2026A wedge Y with mass of 10 kg and all frictionless surfaces and the inclined surface making 37° with horizontal. A block X with mass 2 kg is placed at the highest point of the wedge 2026At t=0 , a body of mass 100 g starts moving under the influence of a force (5 i +10 j ) N. After 2 s its position is (2x i +5y j ) m. The ratio x:y is ______. 2026The time taken by a block of mass m to slide down from the highest point to the lowest point on a rough inclined plane is 50 % more compared to the time taken by the same block on 2026A 0.5 kg mass is in contact against the inner wall of a cylindrical drum of radius 4 m rotating about its vertical axis. The minimum rotational speed of the drum to enable the mass 2026 Full Laws of Motion list All JEE Advanced PYQs