Laws of Motion

A man weighs $80$ kg. He stands on a weighing scale in a lift which is moving upwards with a uniform acceleration of $6 \text{ m/s}^2$. What would be his weight in kg? ($g = 10 \text{ m/s}^2$)

A mass M is hung with a light inextensible string as shown in figure. Find the tension of the horizontal string.

A wooden block of mass M lies on a rough floor. Another wooden block of the same mass is hanging from the point O through strings as shown in the figure. To achieve equilibrium, the co-efficient of static friction between the block on the f...

A block of certain mass is placed on a rough floor. The coefficients of static and kinetic friction between the block and the floor are 0.4 and 0.25 respectively. A constant horizontal force $\mathrm{F}=20 \mathrm{~N}$ acts on it so that th...

A block of certain mass is placed on a rough inclined plane. The angle between the plane and the horizontal is 30$^\circ$. The coefficients of static and kinetic frictions between the block and the inclined plane are 0.6 and 0.5 respectivel...

A body of mass \(10 \mathrm{~kg}\) is kept on a horizontal surface. The coefficient of kinetic friction between the body and the surface is 0.5. A horizontal force of \(60 \mathrm{~N}\) is applied on the body. The resulting acceleration of ...

Two masses of \(5 \mathrm{~kg}\) and \(3 \mathrm{~kg}\) are suspended with the help of massless inextensible strings as shown in figure below.

When whole system is going upwards with acceleration \(2 \mathrm{~m} / \mathrm{s}^2\), the value...

An object with mass \(5 \mathrm{~kg}\) is acted upon by a force, \(\mathbf{F}=(-3 \hat{\mathbf{i}}-4 \hat{\mathbf{j}}) \mathrm{N}\). If its initial velocity at \(t=0\) is $$\mathbf{v}=(3 \hat{\mathbf{i}}+12 \hat{\mathbf{j}}) \mathrm{m} / \m...

A man weighing 60 kg is in a lift moving down with an acceleration of $1.8 \mathrm{~ms}^{-2}$. The force exerted by the floor on him is

A block rests on a rough inclined plane making an angle of $30^{\circ}$ with the horizontal, The coefficient of static friction between the block and the plane is 0.8 . If the frictional force on the block is 10 N , the mass of the block is...

A body of the mass 50 kg is suspended using a spring balance inside a lift at rest. If the lift starts falling freely, the reading of the spring balance is