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A body of mass 50 kg is lifted to a height of 20 m from the ground in the two different ways as shown in the figures. The ratio of work done against the gravity in both the respective cases, will be

Asked in JEE Main 5th April 1st Shift 2024 · Work done by gravity and contact forces

• (1) 1 : 2
• (2) 1 : 1
• (3) √3 : 2
• (4) 2 : 1

Step-by-step solution

Why the other options are wrong

• (1) Comes from thinking the ramp halves the work because it halves the force along the slope; the path is twice as long, so the work is equal.
• (3) Comes from mixing cos 30° of the ramp geometry into a ratio that depends on height alone.
• (4) Comes from thinking the longer ramp path means more work against gravity; friction is absent and only height counts.

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