A sled with a mass of 20 kg is sliding along the snow with a velocity of 5 m/s. What is the momentum of the sled? Question 7 options:

100 kg/ms

4 kg/ms

15 kg/ms

25 kg/ms

100kgms⁻¹

Explanation:

Given parameters:

Mass of the sled  = 20kg

Velocity of the sled  = 5m/s

Unknown:

Momentum of the sled = ?

Solution:

The momentum of a body is the quantity of motion such a body possesses. Due to this;

    Momentum  = mass x velocity

Now insert the parameters and solve;

      Momentum  = 20 x 5  = 100kgms⁻¹

A thermometer is calibrated by using two objects of known temperatures.

The typical process involves using the freezing point and the boiling point of pure water. Water is known to freeze at 0°C and to boil at 100°C at an atmospheric pressure of 1 atm. By placing a thermometer in mixture of ice water and allowing the thermometer liquid to reach a stable height, the 0-degree mark can be placed upon the thermometer.

Similarly, by placing the thermometer in boiling water (at 1 atm of pressure) and allowing the liquid level to reach a stable height, the 100-degree mark can be placed upon the thermometer.

With these two markings placed upon the thermometer, 100 equally spaced divisions can be placed between them to represent the 1-degree marks.

Since there is a linear relationship between the temperature and the height of the liquid, the divisions between 0 degree and 100 degree can be equally spaced.

With a calibrated thermometer, accurate measurements can be made of the temperature of any object within the temperature range for which it has been calibrated.