An open knife edge of mass 'm' is dropped from a height 'h' on a wooden floor. If the blade penetrates upto the depth 'd' into the wood, the average resistance offered by the wood to the knife edge is 

(1) mg

(2) $mg\left(1-\frac{{\displaystyle h}}{{\displaystyle d}}\right)$

(3) $mg\left(1+\frac{{\displaystyle h}}{{\displaystyle d}}\right)$

(4) $mg{\left(1+\frac{{\displaystyle h}}{{\displaystyle d}}\right)}^2$

A body is moving along a straight line by a machine delivering constant power. The distance moved by the body in time t is proportional to 

(1) t^1/2

(2) t^3/4

(3) t^3/2

(4) t²

Two particles of masses m₁ and m₂ in projectile motion have velocities ${\overrightarrow{v}}_1$ and ${\overrightarrow{v}}_2$ respectively at time t = 0. They collide at time t₀. Their velocities become ${\overrightarrow{v}}_1\text{'}$ and ${\overrightarrow{v}}_2\text{'}$ at time 2t₀ while still moving in air. The value of $\left|(m_1\overrightarrow{v_1}\text{'}+m_2\overrightarrow{v_2}\text{'})-(m_1\overrightarrow{v_1}+m_2\overrightarrow{v_2})\right|$ is 

1. Zero

2. $(m_1+m_2)g{t}_0$

3. $2(m_1+m_2)g{t}_0$

4. $\frac{1}{2}(m_1+m_2)g{t}_0$

Consider elastic collision of a particle of mass m moving with a velocity u with another particle of the same mass at rest. After the collision the projectile and the struck particle move in directions making angles θ₁ and θ₂ respectively with the initial direction of motion. The sum of the angles. θ₁ + θ₂, is 

(1) 45°

(2) 90°

(3) 135°

(4) 180°

The relationship between force and position is shown in the given figure (in a one-dimensional case). The work done by the force in displacing a body from \(x = 1\) cm to \(x = 5\) cm is:
      
1.   \(20\) ergs
2.   \(60\) ergs
3.   \(70\) ergs
4.   \(700\) ergs

The pointer reading v/s load graph for a spring balance is as given in the figure. The spring constant is-

(1) 0.1 N/cm

(2) 5 N/cm

(3) 0.3 N/cm

(4) 1 N/cm

Adjacent figure shows the force-displacement graph of a moving body, the work done in displacing body from x = 0 to x = 35 m is equal to-

(1) 50 J

(2) 25 J

(3) 287.5 J

(4) 200 J

A 10kg mass moves along x-axis. Its acceleration as a function of its position is shown in the figure. What is the total work done on the mass by the force as the mass moves from x = 0 to x = 8 cm ?

(1) 8 × 10^–2 joules

(2) 16 × 10^–2 joules

(3) 4 × 10^–4 joules

(4) 1.6 × 10^–3 joules

A toy car of mass 5 kg moves up a ramp under the influence of force F plotted against displacement x. The maximum height attained is given by

1. y_max = 20 m

2. y_max = 15 m

3. y_max = 11 m

4. y_max = 5 m

The graph between the resistive force \(F\) acting on a body and the distance covered by the body is shown in the figure. The mass of the body is \(25\) kg and the initial velocity is \(2\) m/s. When the distance covered by the body is \(4\) m, its kinetic energy would be:

   
1.   \(50\) J
2. \(40\) J
3. \(20\) J
4.   \(10\) J