Physics

A soap bubble of radius 3 cm is formed inside the another soap bubble of radius 6 cm. The radius of an equivalent soap bubble which has the same excess pressure as inside the smaller bubble with respect to the atmospheric pressure is___________________ cm.

The acceleration due to gravity is found upto an accuracy of 4% on a planet. The energy supplied to a simple pendulum of known mass 'm' to undertake oscillations of time period T is being estimated. If time period is measured to an accuracy of 3%, the accuracy to which E is known as_______%.

White light is passed through a double slit and interference is observed on a screen 1.5m away. The separation between the slits is 0.3mm. The first violet and red fringes are formed 2.0mm and 3.5mm away from the central white fringes. The difference in wavelengths of red and violet light is………nm.

If the maximum value of accelerating potential provided by a ratio frequency oscillator is 12 kV. The number of revolution made by proton in a cyclotron to achieve one sixth of the speed of light is_________.

$\left[m_p=1.67*10^{-27}kg,e=1.6*10^{-19}C,Speedoflight=3*10^{8}m\text{?}/\text{?}s\right]$

Two short magnetic dipoles m1 and m2 each having magnetic moment of 1 Am² are placed at point O and P respectively. The distance between OP is 1 meter. The torque experienced by the magnetic dipole m2 due to the presence of m₁ is____________ * 10^-7 Nm.

A source of light is placed in front of a screen. Intensity of light on the screen in I. Two Polaroids P₁ and P₂ are so placed in between the source of light and screen that the intensity of light on screen in   $\raisebox{1ex}{$I$}\!\left/ \!\raisebox{-1ex}{$2$}\right..$ P₂ should be rotated by an angle of_______ (degrees) so that the intensity of light on the screen becomes  

The coefficient of static friction between two blocks is 0.5 and the table is smooth. The maximum horizontal force that can be applied to move the blocks together is_________N.

Consider a badminton racket with length scales as shown in the figure. If the mass of the linear and circular portions of the badminton racket are same (M) and the mass of the threads are negligible, the moment of inertia of the racket about an axis perpendicular to the handle and in the plane of the ring at, $\frac{r}{2}$  distance from the end A of the handle will_________ Mr².

The temperature of equals masses of three different liquids x, y and z are 10°C, 20°C and 30°C respectively. The temperature of mixture when x is mixed with y is 16°C and that when y is mixed with z is 26°C. Temperature of mixture when x and z are mixed will be:

A source and a detector move away from each other in absence of wind with a speed of 20m/s with respect to the ground. If the detector detects a frequency of 1800 Hz of the sound coming from the source, then the original frequency of source considering speed of sound in air 340 m/s will be ……Hz.