A cricket ball of mass 250 g collides with a bat with velocity 10 m/s and returns with the same velocity within 0.01 second. The force acted on bat is 

(1) 25 N

(2) 50 N

(3) 250 N

(4) 500 N

If rope of lift breaks suddenly, the tension exerted by the surface of lift (a = acceleration of lift) 

(1) mg

(2) m(g + a)

(3) m(g – a)

(4) 0

A plumb line is suspended from a ceiling of a car moving with horizontal acceleration of a. What will be the angle of inclination with vertical 

(1) tan^–1(a/g)

(2) tan^–1(g/a)

(3) cos^–1(a/g)

(4) cos^–1(g/a)

The linear momentum p of a body moving in one dimension varies with time according to the equation p = a + bt² where a and b are positive constants. The net force acting on the body is 

(1) A constant

(2) Proportional to t²

(3) Inversely proportional to t

(4) Proportional to t

A block \(A\) of mass \(7\) kg is placed on a frictionless table. A thread tied to it passes over a frictionless pulley and carries a body \(B\) of mass \(3\) kg at the other end. The acceleration of the system will be: (given \(g=10~\text{m/s}^2)\)

A body of weight 2kg is suspended as shown in the figure. The tension T₁ in the horizontal string (in kg wt) is 

(1) $2/\sqrt{3}$

(2) $\sqrt{3}/2$

(3) $2\sqrt{3}$

(4) 2

Two masses m₁ = 5 kg and m₂ = 4.8 kg tied to a string are hanging over a light frictionless pulley. What is the acceleration of the masses when they are free to move (g = 9.8 m/s²) 

(1) 0.2 m/s²

(2) 9.8 m/s²

(3) 5 m/s²

(4) 4.8 m/s²

A block of mass 4 kg is suspended through two light spring balances A and B. Then A and B will read respectively:

(1) 4 kg and zero kg

(2) Zero kg and 4 kg

(3) 4 kg and 4 kg

(4) 2 kg and 2 kg

The mass of a body measured by a physical balance in a lift at rest is found to be m. If the lift is going up with an acceleration a, its mass will be measured as:

1. $m\left(1-\frac{{\displaystyle a}}{{\displaystyle g}}\right)$

2. $m\left(1+\frac{{\displaystyle a}}{{\displaystyle g}}\right)$

3. m

4. Zero

In the arrangement shown in figure, the ends P and Q of an unstretchable string move downwards with uniform speed U. Pulleys A and B are fixed. Mass M moves upwards with a speed 

1. $2U \cos \theta$

2. $U \cos \theta$

3. $\frac{2U}{\cos \theta }$

4. $\frac{U}{\cos \theta }$