# Malaysia SPM Form 5 Physics - Electromagnetism

1.1 Introduction to Magnetism
1.2Straight Wire and Coil
1.3 Solenoid
1.4 Uses of Electromagnet
2.1 Catapult Force
2.2 Application of Catapult Force
3.1 Electromagnetic Induction
3.2 DC and AC Generator
4.1 Transformer
4.2 Transformer - Calculation
5.1 Generation and Transmission of electricity

# Application of Catapult Force

The SPM Physics Workbook is developed under the One-School.net Free Books Project. The content of this book is strictly follow Malaysia SPM (Sijil Pelajaran Malaysia) syllabus. The aim of this project is to provide a complete electronic supplementary network for students to develop self-learning skills by breaking the spoon-feed rituals and to encourage them to compile educational information from the Internet.
1. Which of the following will affect the speed of rotation of a direct current motor?

I.  The number of turns of wire in the coil.
II.  The area of the coil
III.  Strength of the magnetic field.
IV.  The direction of the current.
V.  The magnitude of the current in the coil.
I, III and V only
I, II, III and V only
II, III and IV only
III, IV and V only

2. The diagram shows the structure of a direct current motor. Which of the following is true regarding the part X, Y and Z of the motor?

I. X: to conduct electric current from Z to Y.
II. Y: to change the direction of current in Z in every half revolution.
III. Z: to produce force to rotate the motor.
I, II and III
II and III only
I and II only
I and III only

3. In a direct current motor, the current in the coil changes direction every half rotation. This is done by
the carbon brush
two slip-rings
a split ring commutator
the armature

4. In a direct current motor, the current in the coil changes direction every half revolution. The reason of doing so is
To make the coil rotate faster.
To control the speed of the coil.
To make sure that the coil is always rotates in 1 direction.

5. The diagram shows the structure of a direct current motor. What is the direction of the motion of part Z when the switch is on?
Clockwise
Anticlockwise
Vibrating in between the two magnet.