Straight Objective Type Questions 1. The work done in carrying a body from A to B is 20 J and from B to C is 15J. The work done in moving the body from A to C assuming the force involved in all the cases is conservative force is 1) 35 J 2) 25 J 3) 5 J 4) V175J 2. A small block of mss 'm' is kept on a rough inclined surface of inclination e fixed in an elevator. The elevator goes up with a uniform velocity V and the block does not slide on the wedge. The work done by the force of friction on the bloek in a time t' willI be 1) zero 2) mgvt cos' e 3) mgvt sin 0 4) mgvt sin2e When you lower a book of mass m down slowly through a distance i from yourself, the work done by you on the book is 3. 1) mgh 2) -mgh 3) zero 4) > mgh An open knife edge of mass M is dropped from a height 'h' on a wooden floor. If the blade penetrates a distance 's' into the wood, the average resistance offered by the wood to the blade is h h 1) Mg 2) Mg 1+ 3) Mg 1- h 4) Mg 1+ Numerical value type questions The average resisting force that must act on a 5kg mass to reduce its speed from 65cms to 5. 15 cms in 0.2s is (in N) 6. A box of mass 50kg at rest is pulled up on an inclined plane 12m long and 2m high by a constant Carce of 100N. When it reaches the top of the inclined plane if its velocity is 2ms, the work done against friction in Joules is (o kady of mass 1kg is dropped from a height of Sm on to the ground. If the body penetrates 2em in a the ground, the average resistance ofTered by the ground on to the body is (e 10ms) of 7. = 10ms ) (in N) LEYELJ (ADYANCED)