Grade 9 Physics Ease 2 Prep

How does an ion of oxygen differ from an atom of oxygen?

• The nucleus of the ion has less charge.

• The nucleus of the ion is more positively charged

• The ion has fewer electrons orbiting the nucleus

• The ion has more electrons orbiting the nucleus.

What are two ways to keep the motor running at its original speed?

• decrease both current in the coil and number of turns on the coil

• increase current in the coil but decrease number of turns on the coil

• decrease current in the coil but increase number of turns on the coil

• increase both current in the coil and number of turns on the coil

A nuclide of carbon has the symbol shown. What is the nucleon number of this nuclide of carbon?

• 6

• 20

• 14

• 8

The scattering of alpha-particles from a thin gold foil produces the following observations.

● Most of the alpha-particles pass through the foil.

● Most of the alpha-particles are virtually undeflected.

● A small fraction of the alpha-particles are deflected through large angles.

● A very small fraction of the alpha-particles bounce back from the foil.

Which conclusion follow from these observations?Which conclusion follow from these observations?

• Small amount of the atom is empty space.

• The nucleus consists of protons and neutrons.

• Most of the mass of the gold atom is outside of its nucleus.

• The nucleus must be charged.

What component is a part of a DC motor but not of a simple AC generator with moving coils?

• the brushes

• the split-ring commutator

• the coil

• the magnet

A transformer has 6600 turns on the primary coil and 600 turns on the secondary coil. The output of the secondary coil is 200 V a.c. and is connected to a heater. The transformer is 100% efficient. The heater produces a power of 2640 W. What is the current in the primary coil?

• 1.2 A

• 1.1 A

• 0.12 A

• 0.11 A

Fission and fusion are two types of nuclear process. Which reaction has the total mass of the nuclides produced same with the total mass of the original nuclide or nuclides in these nuclear processes?

• Fusion only

• Fission only

• Both fission and fusion

• None of them

The diagram shows a wire hanging freely between the poles of a magnet. There is a current in the wire flowing in upward direction. The magnet and current cause a force to act on the wire. In which direction does this force act?

• into the page (away from you)

• to the right

• to the left

• out of the page (toward you)

The diagram shows the pattern of the magnetic field due to the current I in a straight wire. Which statement is correct?

• If I is flowing downward, then Y is the direction of magnetic field around I and magnetic field is stronger at P than Q.

• If I is flowing downward, then X is the direction of magnetic field around I and magnetic field is stronger at P than Q.

• If I is flowing upward, then Y is the direction of magnetic field around I and magnetic field is stronger at Q than P.

• If I is flowing upward, then X is the direction of magnetic field around I and magnetic field is stronger at Q than P.

A step-down transformer is 100% efficient. It has an input voltage of 120 V a.c. and an output voltage of 40 V a.c. The current in the primary coil is 0.50 A.

What is the current in the secondary coil?

• 2.0 A

• 0.16 A

• 1.5 A

• 3.0 A