Y9- Revision 9

Sound travels fastest in ............... and slowest in ...............

An .................... occurs when a sound wave is reflected.

The states of matter that are fluids are .................... and ..............

............................. is the heat transfer method which does not involve particles.

In a circuit. there is a 3.0 Ω resistor and a 7.0Ω resistor connected to a 5.0V battery.

What is the current in the battery?

Why are lamps in a house lighting circuit connected in parallel rather than in series?

• When more lamps are added, their brightness decreases.

• The lamps can be turned off independently using switches

• Less current is taken from the power supply.

• If one lamp stops working, the remaining lamps become brighter.

Which of the following combinations will not results in a displacement reaction?

• Silver and potassium nitrate

• Magnesium and copper sulfate

• Zinc and magnesium nitrate

• Copper and zinc nitrate

The Giant Impact theory (Collision theory) states that the Earth was hit by something huge and a piece of the Earth was ejected into space.

• True

• False

A boundary where plates move away from each other is called ......................

How do the plates move at a transform boundary?