List of top Physics Questions asked in KCET

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 \( F = 20 \, \text{N} \) acts on it so that the velocity of the block varies with time according to the following graph. The mass of the block is nearly (Take \( g = 10 \, \text{m/s}^2 \)): 

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 coefficient of static friction between the block on the floor and the floor itself is 

The circuit shown in the figure contains two ideal diodes \( D_1 \) and \( D_2 \). If a cell of emf 3V and negligible internal resistance is connected as shown, then the current through \( 70 \, \Omega \) resistance (in amperes) is: 

The graph between variation of resistance of a wire as a function of its diameter keeping other parameters like length and temperature constant is 

While determining the coefficient of viscosity of the given liquid, a spherical steel ball sinks by a distance \( x = 0.8 \, \text{m} \). The radius of the ball is \( 2.5 \times 10^{-3} \, \text{m} \). The time taken by the ball to sink in three trials are tabulated as shown: 

In an experiment to determine the figure of merit of a galvanometer by half deflection method, a student constructed the following circuit. He applied a resistance of \( 520 \, \Omega \) in \( R \). When \( K_1 \) is closed and \( K_2 \) is open, the deflection observed in the galvanometer is 20 div. When \( K_1 \) is also closed and a resistance of \( 90 \, \Omega \) is removed in \( S \), the deflection becomes 13 div. The resistance of galvanometer is nearly: 

When a bar magnet is pushed towards the coil, along its axis, as shown in the figure, the galvanometer pointer deflects towards X. When this magnet is pulled away from the coil, the galvanometer pointer 

If \( r \) and \( r' \) denote the angles inside the prism having angle of prism \( 50^\circ \), considering that during the interval of time from \( t = 0 \) to \( t = T \), \( r \) varies with time as \( r = 10^\circ + t^2 \). During this time \( r' \) will vary with time as 

A convex lens has power \( P \). It is cut into two halves along its principal axis. Further, one piece (out of two halves) is cut into two halves perpendicular to the principal axis as shown in the figure. Choose the incorrect option for the reported lens pieces. 

A metallic sphere of radius \( R \) carrying a charge \( q \) is kept at a certain distance from another metallic sphere of radius \( R_4 \) carrying a charge \( Q \). What is the electric flux at any point inside the metallic sphere of radius \( R \) due to the sphere of radius \( R_4 \)? 

Charges are uniformly spread on the surface of a conducting sphere. The electric field from the center of the sphere in a point outside the sphere varies with distance \( r \) from the center as 

The variations of resistivity \( \rho \) with absolute temperature \( T \) for three different materials X, Y, and Z are shown in the graph below. Identify the materials X, Y, and Z. 

Which of the following graphs represent the variation of magnetic field \( B \) with perpendicular distance \( r \) from an infinitely long, straight conductor carrying current? 

The anode voltage of a photocell is kept fixed. The frequency of the light falling on the cathode is gradually increased. Then the correct graph which shows the variation of photo current \( I \) with the frequency \( f \) of incident light is 

If AB is incident plane wave front, then refracted wave front is (n\(_1\) → n\(_2\)) 

Match the following types of nuclei with examples shown: 

Two flywheels are connected by a non-slipping belt as shown in the figure. \(m_1 = 4 \, \text{kg}\), \(r_1 = 20 \, \text{cm}\), \(m_2 = 20 \, \text{kg}\), \(r_2 = 30 \, \text{cm}\). A torque of 10 Nm is applied on the smaller wheel. Then match the entries of column I with appropriate entries of column II. 

Three metal rods of the same material and identical in all respects are joined as shown in the figure. The temperatures at the ends of these rods are maintained as indicated. Assuming no heat energy loss occurs through the curved surfaces of the rods, the temperature at the junction is 

The variations of kinetic energy \( K \), potential energy \( U \), and total energy \( E \) as a function of displacement of a particle in SHM is shown in the figure. The value of \( x_3 \) is 

You are given a dipole of charge \( +q \) and \( -q \) separated by a distance \( 2l \). A sphere 'A' of radius \( R \) passes through the centre of the dipole as shown below and another sphere 'B' of radius \( 2R \) passes through the charge \( +q \). Then the electric flux through the sphere A is