Question no. 1

A stone, a bucket, a cat, a balloon, a salt crystal, a windowpane, a lump of ice, a cloud of steam, an aeroplane are:

objects,

substances,

amorphous solids,

bodies?

Question no. 2

Air, carbon dioxide, neon, helium, oxygen, nitrogen, xenon, radon, krypton at a temperature of 20 degrees of Celsius are:

liquids,

solids,

gases,

crystals?

Question no. 3

A force of 1N accelerates a standard kilogram mass with an acceleration of:

1 m/s²,

9.81 m/s²,

10 m/s²,

0.1 m/s².

Question no. 4

Water, glass, iron, steel, sulphur, sugar, table salt, kerosene, petrol ( gasoline ) are:

substances,

bodies,

amorphous solids,

objects?

Question no. 5

A body has been thrown into a container full of some liquid and has sunk. Which of the following comments is correct?

There is no buoyant force acting on the body, since it has sunk.

The body has sunk, because its weight exceeds the buoyant force.

The body has sunk, because its density is less than of the liquid.

Since the body has sunk, a volume of the liquid must have overflowed from the container and could not increase the buoyant force.

Question no. 6

Accelerated motion is a motion in which the velocity changes. Which of the following comments on the motion is correct?

For the motion, the velocity is increasing and the acceleration is positive.

For the motion, the velocity is decreasing and the acceleration is negative .

For the motion, the acceleration can be negative, if the velocity is decreasing, or positive, if the velocity is increasing.

For the motion, the acceleration can be negative, if the velocity is increasing, or positive, if the velocity is decreasing.