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WorksheetsPhysics KBSM Form 5: 2.5 Electric power & energy
Total questions: 25
Worksheet time: 42mins
What is the energy possessed by a charge due to its position in an electric field?
electrical potential energy
electrical kinetic energy
electrical mechanical energy
electrical potential difference
Electric energy is the energy carried by electric charges to _____________ in a complete circuit having potential difference, V.
flow current
do work
move between two points
change form
Electric power is....
rate of electrical energy transform to another type of energy.
ability to do work in electric circuit
rate of flow of charges in electric circuit
ability to change the form of electrical energy to another type of energy
kilowatt hour is equal to
1000 W for 3600 s
10000 W for 1 hour
1 kg for 1 hour
500 W for 3600 s
1 unit is equal to one kilowatt-hour [kWh], also equal to ____________ [joules].
3,600 J
360,000 J
3,600,000 J
360,000,000 J
Efficiency is...
The percentage of energy that is actually used to do work
The ability of electrical appliances to keeps energy in
Keep refrigerator doors open in long time, high power bulbs at car porch, disable timer on air-conditioning, ironing clothes in small quantities. These actions will cause...
low energy efficiency
low electrical energy consumption
high energy efficiency
lower monthly electric bill
Which of the following energy transformations occur when you switch on a ceiling fan?
Kinetic to light
Electrical to kinetic
Electrical to light
Kinetic to electrical
A lamp changes __________ energy into light and heat energy.
Kinetic
Electrical
Sound
Chemical
What is the unit of electrical power?
Watt
Volt
Ampere
Ohm
One Terawatt is equivalent to:
106 W
109 W
1012 W
1010 W
What will be the current drawn by an electric bulb of 1000 W when it is connected to a source of 220 V?
4.55 A
0.22 A
2.20 A
45.50 A
A current of 4 A flows through a 20 V car headlight bulb. Calculate the electric power.
80 W
5 W
50 W
0.2 W
Calculate the electric power of an electrical appliance in which 10 A of current is flowing through a resistor of 2 ohms.
80 W
200 W
20 W
50 W
Calculate the electric power of an electrical appliance of 20 V having a resistance of 10 ohms.
200 W
40 W
4000 W
5 W
Calculate the electrical energy consumed when a potential difference of 5 V is applied across a resistor of 2 ohms for 30 minutes.
375 J
375 kJ
225000 J
22.5 kJ
A current of 0.5 A flows through a resistance of 10 ohms for half an hour. Find the amount of electrical energy consumed by the resistance.
Remember:
V = IR
P = VI
E = Pt
22500 J
4500 J
75 J
45 J
An electric meter reads 3462 kWh at the end of the month while a month ago it read 3396 kWh. How many units of electrical energy have been consumed during the month? Find the cost of electrical energy consumed if 1 unit of energy costs RM0.38
66 kWh = 66 units; RM25.08
33 kWh = 33 units; RM12.54
66 kWh = 33 units; RM12.54
33 kWh = 66 units; RM25.08
An electric appliance is labelled 12 V, 9 W.
How much electrical charges flow through the electric appliance in 10 minutes?
7.5 C
13.3 C
800 C
450 C
How much power is dissipated in the resistor when the switch is closed? [ignore the internal resistance value]
0.8 W
1.2 W
7.2 W
30.0 W
"Energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another". This statement refer to....
Principle of Energy
Principle of Power
Principle of Conservation of Momentum
Principle of Conservation of Energy
An electrical appliance labelled 240V, 450W. What is that means?
When 240 V of potential difference supplied, 450W of power generated.
When 240 V power supplied , 450W of potential difference generated.
Write down your answers in RMXXX.XX
(a)
