The length covered by a body is found to be directly proportional to square of time. What is the nature of acceleration?

The distance covered by a body moving along a straight line is proportional to the square of time. The acceleration of the body is

If in case of a motion, displacement is directly proportional to the square of time elapsed, what do you think about its acceleration i.e., constant or variable? Explain why?

Prove that velocity of gas molecule is directly proportional of the square root of temperature.

If a force of 30 Newton is applied on a body of mass 15 kg. What will be its acceleration?

The length of a copper rod at 20°C is found to be 150cm when measured with a steel scale which gives correct reading at this temperature.What length of the same copper rod be found when measured with the same rod at 60°C?

A brass rod of length 50 cm and diameter 3.0 mm is joined to a steel rod of the same length and diameter. What is the change in length of the combined rod at 250 ^@C , if the original lengths are at 40.0 ^@C ? Is there a ‘thermal stress’ developed at the junction? The ends of the rod are free to expand (Co-efficient of linear expansion of brass = 2.0 xx 10^-5K^-1 steel = 1.2 xx 10^-5 K^-1) .

We wish to obtain an erect image of an object, using a concave mirror of focal length 15cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.

A steel tape 1m long is correctly calibrated for a temperature of 27.0 ^@C . The length of a steel rod measured by this tape is found to be 63.0 cm on a hot day when the temperature is 45.0 ^@C . What is the actual length of the steel rod on that day? What Is the length of the same steel rod on a day when the temperature is 27.0 ^@C ? Coefficient of linear expansion of steel = 1.20xx10^-5 K^-1 .