A mass of M kg is suspended by a weightless string. The horizontal… | JEE Main 2006 (AIEEE)

Q36JEE Main 2006 · AIEEEMedium

Conservation of Energy

A mass of $M\text{ kg}$ is suspended by a weightless string. The horizontal force that is required to displace it until the string makes an angle of $45^\circ$ with the initial vertical direction is

Show answer and solution

Answer: (d)

A constant horizontal force $F$ takes the mass from rest at the bottom to rest at $45^\circ$ : work by $F$ = gain in PE.
Horizontal shift $= L\sin 45^\circ$ , rise $= L(1 - \cos 45^\circ)$ .
$F \cdot \frac{L}{\sqrt{2}} = MgL\left(1 - \frac{1}{\sqrt{2}}\right)$
$F = Mg(\sqrt{2} - 1)$ . So the answer is (d).

Report a mistake

More questions on Conservation of Energy

A spherical ball of mass 20 kg is stationary at the top of a hill of height 100 m. It…JEE Main 2005 (AIEEE)
The upper half of an inclined plane with inclination φ is perfectly smooth while the…JEE Main 2005 (AIEEE)
A ball of mass 2 kg and another of mass 4 kg are dropped together from a 60 feet tall…NEET 2004 (AIPMT)
A uniform chain of length 2 m is kept on a table such that a length of 60 cm hangs freely…JEE Main 2004 (AIEEE)
A ball whose kinetic energy is E, is projected at an angle of 45° to the horizontal. The…JEE Main 2002 (AIEEE)
A particle is projected making an angle of 45° with horizontal having kinetic energy K…NEET 2001 (AIPMT)
A child is sitting on a swing. Its minimum and maximum heights from the ground 0.75 m and…NEET 2001 (AIPMT)
A particle is projected making an angle of 45° with horizontal having kinetic energy K…NEET 1997 (AIPMT)

Conservation of Energy question from JEE Main 2006 (AIEEE)

More questions on Conservation of Energy