Physics Test - ...

A train travelling at 72 kmph has to be brought to rest within a distance of 200 metres. The required retardation is

In the figure given below, curves AB and CD represent the relation between pressure P and volume V of an ideal gas. Which of the following curves represent(s) an adiabatic expansion?

Directions:In the following question, Statement - 1 (Assertion) is followed by Statement - 2 (Reason). The question has the following four choices, out of which only one choice is correct.

Statement - 1:The figure shows the current-voltage (I – V) graph for a given metallic wire at two different temperatures T1and T2. It follows from the graph that T2is greater than T1.

Statement - 2: The resistance of a metallic conductor increases with increase in temperature.

A spherical surface of radius of curvature R separates air (refractive index 1.0) from glass (refractive index 1.5). The centre of curvature is in the glass. A point object P placed in air is found to have a real image Q in the glass. The line PQ cuts the surface at point O and PO = OQ. The distance PO is equal to

Two water droplets coalesce to form a large drop. In this process,

An unknown resistance R1 is connected in series with a resistance of 10Ω . This combination is connected to one gap of a metre bridge, while a resistance R₂ is connected in the other gap. The balance point is at 50 cm. Now, when the 10Ω resistance is removed, the balance point shifts to 40 cm. The valve of R₁ is (in ohms)

An ideal gas heat engine operates in a Carnot's cycle between 227 × C and 127 × C. It absorbs 6 x 104 J heat at high temperature. The amount of heat converted into work is

A telescope has an objective lens of focal length 200 cm and an eye piece of focal length 2 cm. If this telescope is used to see a 50 m tall building at a distance of 2 km, what is the height of the image of the building formed by the objective lens ?

Two blocks of masses m₁ = 5 kg and m₂ = 6 kg are connected by a light string passing over a light frictionless pulley as shown in the figure. The mass m₁ is at rest on the inclined plane and mass m2 hangs vertically. If the angle of inclination is θ = 30°, what is the magnitude and direction of the force of friction on the 5 kg block? Take g = 10 ms^–2.

An engine has an efficiency of 1/6. When the temperature of the sink is reduced by 62^oC, its efficiency is doubled. The temperature of the source is