revision grade 9 u 1

Speed measuring unit is ------------ while the measuring unit of acceleration is-----

Force is a---------- physical quantity, while mass is a ------------physical quantity.

A car starts movement from rest until its speed reaches 25 m/s after 10 seconds."

1. Calculate the value of acceleration.

2. What kind is the acceleration?

scientific term:

A vector quantity that equals the displacement in one second.

What happens in the following cases:

If an object moves at a regular speed, what is the value of its acceleration?

An object moves according to the graphical relation shown in the opposite figure, calculate

1. The speed of the object's motion and mention its kind.

2. The time that the object takes to cover a distance of 15 meters.

3. The distance that the object covers in 4 seconds.

If the speed of a car is 36 km/h, it means that its speed is --------------m/s

Give reasons for:

The moving car seems stable to the observer who moves at the same speed and direction.

Give reasons for:

Pilots take in consideration the velocity and the direction of the wind

Mention one usage for each of the following:

The speedometer.