grade 4 , con 6 , lesson 2

The measuring units of distance are..........

• second and meter.

• hour and kilometer.

• hour and second.

• kilometer and meter.

...............and ............ are the main factors that we need to calculate the speed of an object

• time - kinetic energy

• distance - kinetic energy

• distance - time

• kinetic energy - potential energy

How can we calculate the speed of an object?

• Speed = distance + time

• Speed = distance x time

• Speed = distance ÷ time

• Speed = distance - time

Which of the following is a measuring unit of speed?

• hr/km.

• sec/m.

• kg/sec.

• m/sec.

What is the speed of a car that travels 400 meters in 4 second?

• 100 m/sec.

• 20 m/sec.

• 30 m/sec.

• 40 m/sec.

When the kinetic energy of a moving body........ , its speed...........

• increases - doesn't change.

• increases - increases.

• decreases - doesn't change.

• decreases - increases.

As the angle of a ramp decreases, the speed of a toy car rolling on it ...........and its kinetic energy..........

• increases - decreases.

• increases - increases.

• decreases - decreases.

• decreases - increases.

An object keeps moving with same speed when............

• its kinetic energy decreases.

• its potential energy increases.

• no another force stops it.

• another object collides with it.

If the angle of inclination of a hill increases, the kinetic energy of an object moving down it will

• decrease.

• increase.

• remain as it is.

• be destroyed.

We can use the speed of an object to know the .......energy of this object

• thermal

• kinetic

• Potential

• Sound