1 markWhich definition is correct and uses only quantities rather than units?
Density is mass per cubic metre
Potential difference is energy per unit current
Pressure is force per unit area
Speed is distance travelled per second
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1 markWhat is a reasonable estimate of the average gravitational force acting on a fully grown woman standing on the Earth?
60 N
250 N
350 N
650 N
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1 markA physical quantity has the symbol V and the unit m3. Which physical quantity does the V represent?
Potential difference
Velocity
Pressure
Volume
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1 markWhich answer option gives a reasonable estimate of the number of seconds in a year?
3×107
5×105
1×106
7×108
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1 markA physical quantity has the unit m s−2 and the symbol a. What is the correct name for this quantity?
Activity of a radioactive source
Amplitude
Avogadro constant
Acceleration
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1 markFor which quantity is the magnitude a reasonable estimate?
Frequency of a radio wave 500 p Hz
Mass of an atom 500 μg
The Young modulus of a metal 500 kPa
Wavelength of green light 500 nm
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1 markWhat is a reasonable estimate for the volume of 1 ml of water?
0.1 cm3
1 cm3
10 cm3
100 cm3
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1 markWhat is the symbol and the units for the gravitational constant?
Symbol: G
Units: N m2 kg−2
Symbol: g
Units: N kg−1
Symbol: g
Units: m s−2
Symbol: 
Units: J kg−1
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1 markAn adult male stands with a litre carton of milk balanced on his head.
What is a reasonable estimate of the gravitational potential energy of the milk carton?
2 J
20 J
200 J
2000 J
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1 markWhich of the following answer options provides a reasonable estimate for the density of a sugar cube?
0.01 kg m−3
0.1 kg m−3
10 kg m−3
1000 kg m−3
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1 markWhich estimate is realistic?
The kinetic energy of a bus travelling on an expressway is 30 000 J
The power of a domestic light is 300 W
The temperature of a hot oven is 300 K
The volume of air in a car tyre is 0.03 m3
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1 markWhich statement is incorrect by a factor of 100 or more?
Atmospheric pressure is about 1 × 105 Pa
Light takes 5 × 102 s to reach us from the Sun
The frequency of ultraviolet light is 3 × 1012 Hz
The life-span of a man is about 2 × 109 s
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1 markA boy jumps from a wall 5 m high. What is a reasonable estimate of the change in momentum of the boy when he lands without rebounding?
4 × 100 kg m s–1
4 × 101 kg m s–1
4 × 102 kg m s–1
4 × 103 kg m s–1
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1 markWhich of the following answer options give a reasonable estimate for the time taken for light to cross the nucleus of a hydrogen atom?
3 × 10−28 s
3 × 10−24 s
3 × 10−20 s
3 × 10−16 s
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1 markThe depth of the Mariana Trench is estimated to be around 11 000 m. Which of the following answer options provides a reasonable estimate of the total pressure at the bottom of the Mariana Trench?
1 ×106 Pa
1 ×107 Pa
1 ×108 Pa
1 ×109 Pa
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