Physics Test 24...

A ball of mass 0.25 kg attached to the end of a string of length 1.96 m is moving in a horizontal circle. The string will break if the tension is more than 25 N. What is the maximum speed with which ball can be moved?

Two wires A and B are of the same materials. Their lengths are in the ratio 1 : 2 and the diameters are in the ratio 2 : 1, When stretched by force F_A and F_B respectively they get equal increase in their lengths. Then the ratio  should be:

In a capillary tube of radius 'R', a straight thin metal wire of radius 'r' (R > r) is inserted symmetrically and one end of the combination is dipped vertically in water such that the lower end of the combination is at same level. The rise of water in the capillary tube is [T = surface tension of water, ρ = density of water, g = gravitational acceleration]

A circuit connected to an ac source of emf e = e₀ sin(100t) with t in seconds, gives a phase difference of  between the emf e and current i. Which of the following circuits will exhibit this ?

A mass of 100g strikes the wall with speed 5m/s at an angle as shown in figure and it rebounds with the same speed. If the contact time is 2 × 10⁻³sec, what is the force applied on the mass by the wall.

A wire of length ‘l’ and resistance 100 Ω is divided into 10 equal parts. The first 5 parts are connected in series while the next 5 parts are connected in parallel. The two combinations are again connected in series. The resistance of this final combination is:

Electrons used in an electron microscope are accelerated by a voltage of 25 kV. If the voltage is increased to 100 kV then the de-Broglie wavelength associated with the electrons would

A metal target with atomic number Z = 46 is bombarded with a high energy electron beam. The emission of X-rays from the target is analyzed. The ratio r of the wavelengths of the K_α-line and the cut-off is found to be r = 2. If the same electron beam bombards another metal target with Z = 41, the value of r will be

If two traveling waves, given by

𝑦₁ = 𝐴₀sin(𝑘𝑥 − 𝜔𝑡) and 𝑦₂ = 𝐴₀sin(α𝑘𝑥 − β𝜔𝑡)

are superposed, which of the following statements is correct?

A transverse wave is represented by the equation   For what value of λ the maximum particle velocity is equal to two times the wave velocity