Science Quiz Bee

Which of the following is an advantage of friction?

• It wears down moving machine parts.

• It reduces force.

• It enables us to hold any object.

• It produces excessive heat.

What are the factors that affect the magnitude of friction?

• I and III

• I and IV

• II and III

• III and IV

The diagram shows a lever balanced by two objects, X and Y. If the weight of Y is increased to 10 N, what is the weight of X in order to balance the lever?

• 7.5 N

• 20 N

• 30 N

• 150 N

Which of the following is an advantage of friction?

• It wears down moving machine parts.

• It reduces force.

• It enables us to hold a glass.

• It produces excessive heat

1 kg of object in the Earth’s gravitational field experiences a force of about ______.

• 7 N

• 20 N

• 100 N

• 9.8 N

Which of the following is correct about vector quantity?

• It has only magnitude.

• It has only direction.

• It has both magnitude and direction.

• It has no magnitude and no direction.

The information describes one of the layers of the Earth. What is the layer?

• Makes up about 70% of the Earth’s mass

• Made up of silicon, magnesium, oxygen and iron

• Crust

• Mantle

• Outer Core

• Inner Core

A car travels at uniform velocity a distance of 100 m in 4 seconds. What is the velocity of the car?

• 20 m/s

• 25 m/s

• 104 m/s

• 400 m/s

What is the difference between speed and velocity?

• Velocity is the distance traveled with a direction while speed is the distance traveled without a direction.

• Velocity is the total distance traveled for a period of time while speed is the distance

  traveled per hour.

• Velocity is the rate of change of displacement while speed is the rate of change of distance.

• Velocity is a scalar quantity while speed is a vector quantity.

In which of the following activities is zero work done?

• Rowing a boat downstream

• Rowing a boat upstream

• Carrying a flower pot and going up the stairs

• Carrying a box and walking along a horizontal surface