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Find the difference in heights in limbs as shown in the given data. Surface tension T =7.3 × 10⁻² N/m, the density of water ρ = 1000 Kg/m³ and the angle of contact θ = 0°.

a. 1.19 mb. 2.19 mc. 3.19 md. 4.19 mSolution: Answer: (b)... View Article

The backside of a truck is open and a box of 40 kg is placed 5 m away from the rear end. The coefficient of friction of the box with the surface of the truck is 0.15. The truck starts from rest with 2 m/s² acceleration. Calculate the distance covered by the truck when the box falls off

1) 20 m 2) 30 m 3) 40 m 4) 50 m Answer: 1) 20 m Solution: Given, Mass of the box = 40 Kg S = 5m Coefficient of friction of the box... View Article

Two masses 8 kg and 12 kg are connected at the two ends of a string that goes over a frictionless pulley. Calculate the acceleration of the masses and the tension in the string. (take, g =10 m/s²)

1) 8 m/s2 , 144 N 2) 4 m/s2 , 112 N 3) 6 m/s2 , 128 N 4) 2 m/s2 , 96 N Answer: 4) 2 m/s2 , 96 N Solution: The larger mass 12 kg... View Article

An object is gently placed on a long conveyor belt moving with 11 ms^-1. If the coefficient of friction is 0.4, then the block will slide in the belt up to a distance of

1) 10.21 m 2) 15.125 m 3) 20.3 m 4) 25.6 m Answer: Given, u = 11m/s Coefficient of friction = 0.4 Velocity of the belt w.r.t... View Article

A mass M kg is suspended by a weightless string. The horizontal force required to hold the mass at 60° with the vertical is

1) Mg 2) Mg√3 3) Mg(√3 +1) 4) Mg/√3 Answer: 2) Mg√3 Solution: The tension acting on the string at... View Article

A block of mass 2 kg rests on a horizontal surface. If a horizontal force of 5 N is applied on the block, the frictional force on it is ( take, µ_k = 0.4, µ_s = 0.5 )

1) 5 N 2) 10 N 3) 8 N 4) zero Answer: 3) 8 N Solution: F = μkmg = 0.4 x 2 x 10 = 8N Therefore, frictional force = 8 N... View Article

A uniform metal chain is placed on a rough table such that one end of it hangs down over the edge of the table. When one-third of its length hangs over the edge, the chain starts sliding. Then, the coefficient of static friction is

1) 3/4 2) 1/4 3) 2/3 4) 1/3 5) 1/2 Answer: 5) 1/2 Solution: Coefficient of friction, μ= F/R = ... View Article

The engine of a car produces an acceleration of 6ms^-2 in the car. If this car pulls another car of the same mass, then the acceleration would be

1) 6 ms-2 2) 12 ms-2 3) 3 ms-2 4) 1.5 ms-2 Answer: 3) 3 ms-2 Solution: Let the mass of the car be M The maximum force applied by the... View Article

A steel wire can withstand a load up to 2940 N. A load of 150 kg is suspended from a rigid support. The maximum angle through which the wire can be displaced from the mean position so that the wire does not break when the load passes through the position of equilibrium is

1) 30° 2) 60° 3) 80° 4) 85° Answer: 2) 60° Solution: T cos θ = mg ⇒ cos θ = mg/T =... View Article

A shell initially at rest explodes into two pieces of equal mass, the two pieces will

1) move with different velocities in different directions 2) move with the same velocity in opposite directions 3) move with the same velocity... View Article

A rocket of mass 1000 kg is exhaust gases at a rate of 4 kgs^-1 with a velocity of 3000 ms^-1. The thrust developed on the rocket is

1) 12000 N 2) 120 N 3) 800 N 4) 200 N Answer: 1) 12000 N Solution: F = V (dm/dt) = 3000 x 4 = 12000 N... View Article

Three guns are aimed at the centre of a circle. They are mounted on the circle, 120° apart. The fire in a timed sequence, such that the three bullets collide at the centre and mash into a stationary lump. Two of the bullets have identical masses of 4.5 g each and speeds of v₁ and v₂. The third bullet has a mass of 2.50 g and a speed of 575 ms^-1. Find the unknown speeds.

1) 200 ms-1 each 2) 145 ms-1 and 256 ms-1 3) 536 ms-1 and 320 ms-1 4) None of the above Answer: 4) None of the above Solution: Since... View Article

Diwali rocket is ejecting 50 g of gases per second at a velocity of 400 ms^-1. The accelerating force on the rocket will be

1) 22 dyne 2) 20 N 3) 20 dyne 4) 100 N Answer: 2) 20 N Solution: The acceleration force on the rocket = upward thrust =... View Article

A shell at rest at the origin explodes into three fragments of masses 1 kg, 2 kg and kg. The 1 kg and 2 kg pieces fly off with speeds of 5 ms^-1 along the x-axis and 6 ms^-1 along the y-axis respectively. If the m kg piece flies off with a speed of 6.5 ms^-1, the total mass of the shell must be

1) 4 kg 2) 5 kg 3) 3.5 kg 4) 4.5 kg 5) 5.5 kg Answer: 2) 5 kg Solution: Let the mass of the shell be M which will be the sum of the masses... View Article

A train is moving with a velocity of 20 m/s on this dust is falling at the rate of 50 kg/min. The extra force required to move this train with a constant velocity will be

1) 16.66 N 2) 1200 N 3) 1000 N 4) 166.6 N Answer: 1) 16.66 N Solution Force, F = v x (dm/dt) = 20 x (50/60) = 50/3 = 16.67 N... View Article

If the resultant of all the external forces acting on a system of particles is zero, then from an inertial frame, one can surely say that

1) linear momentum of the system does not change in time 2) kinetic energy of the system does not change in time 3) angular momentum of the... View Article

A player kicks a football of mass 0.5 kg and the football begins to move with a velocity of 10 m/s. If the contact between the leg and the football lasts for 1/50 s, then the force acted on the ball should be

1) 2500 N 2) 1250 N 3) 250 N 4) 625 N Answer: 3) 250 N Solution: Force = Change in momentum/Time = (0.5 x 10) - (0.5 x 0) / 1/50 = 5... View Article

A truck is moving on a frictionless surface with a uniform velocity of 10 ms^-1. A leak occurs in the water tank of the truck at the rate of 2 kgs^-1. What is the speed of the truck after 50 s, if the mass of the truck is 100 kg and the mass of water in the truck initially was 100 kg?

1) 20 m/s 2) 10 m/s 3) 15 m/s 4) None of these Answer: 1) 20 m/s Solution: Mass of the system, M = 100 + 100 = 200 Kg Water leaks at a rate... View Article

Assume an ideal gas is taken from the state from A to state B. The process is isothermal. Then the corresponding P-T graph will be

Solution: Answer: (c)As T = constant, soP ∝ 1/V... View Article

Two wires of equal length with diameter 2 mm each having resistivity ρ₁ = 12 μΩ. cm and ρ₂ = 51 μΩ. cm respectively. They are connected in parallel so that their equivalent resistance is 3 Ω. Find the length of the wire.

a. 50 mb. 97 mc. 197 md. 291 mSolution: Answer: b... View Article