Unit - 1.3 Measurement of Density and Speed — PHYSICS STD 7 — Question

Given below statement is incorrect. Write the correct statement :
When a body covers equal distances in equal intervals of time in a specified direction, it is said to be moving with uniform speed.

Give an example where electrical energy gets converted to sound energy.

Explain the following :Why are ice blocks wrapped in saw dust of woolen blanket?

Sublimation

Arrange the following substances in order of their increasing density:
(a) iron
(b) cork
(c) brass
(d) water
(e) mercury

A person walking in a compartment of a stationary train is relative to the compartment and is relative to the platform.

State the energy changes that occur in the following :
Lighting of a torch bulb.

A train covers a distance of 820 km with a speed of 80 km/h. How long does it take to finish the journey?

Given below statement is incorrect. Write the correct statement :
During the charging of a inverter battery, the chemical energy changes into electric energy.

Name the energy possessed by a flowerpot placed at the rooftop of a building