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Chapter 1
Chapter 2
Chapter 3
Chapter 4
100
What is the atomic mass of hydrogen? a. 1 b. 10 c. 100
a. 1
100
For a beam in equilibrium the sum of the positive moments about a point = the sum of the ...... moments about the same point.
Negative
100
What is the displacement of an object travelling at 5m/s after 2 minutes? a. 10m b. 600m c. 6000m
b. 600m
100
If (x + 6)(x - 3) =0 what are the values of x?
-6 and 3
200
If the atomic mass of carbon is 12 and the atomic mass of oxygen is 16 what is the atomic mass of CO2
44
200
A force of 100N acts on a rod and perpendicular to it. The distance from the support of the rod to the force is 6m. What is the moment of the force about the rod's support?
600Nm
200
A tensile force of 100N is applied to a rod with a cross sectional area of 0.1sqm. What is the stress in the rod?
1000 N/sqm
200
A cannon fires a cannon ball at an angle of 60 degrees to the horizontal. If the velocity of the cannon ball is 50m/s what is its horizontal velocity?
25m/s
300
If the threshold of hearing Io = 10-12 Wm-2 what is the level in decibels of a sound with intensity I=10-4 Wm-2, where I (dB) = 10log[I/Io]
80dB
300
A force of 50N acts at an angle of 40 degrees to the horizontal. What is the magnitude of its horizontal component? a. 50cos40degrees b. 50sin40degrees c. 50tan40degrees
a. 50cos40degrees
300
A ball is dropped from a height of 80m. How long will it take to reach the ground? Use g = 10m/second squared and s=1/2 x a x t x t.
4 seconds
300
What are the factors of x squared + 9x +18? a. (x-3)(x-6) b. (x+3)(x+6) c. (x+3)(x-6)
b. (x + 3)(x + 6)
400
An earthquake is measured with a wave amplitude A. A is 392 times larger than Ao. What is the magnitude of this earthquake using the Richter scale R = log[A/Ao]? a. 0.259 b. 2.59 c. 25.9
b. 2.59
400
A concrete column with a cross sectional area of 0.64 square metres is 5m tall and has a density of 2400kg/cubicmetre. What is its mass in kg? a. 7680kg b. 76800kg c. 768kg
a. 7680
400
A steel wire of initial length 2m extends by 20mm when a tensile force is applied. What is the strain in the wire? a. 0.01 b. 0.01m c. 0.001
a. 0.01
400
Factorise 12y² – 20y + 3
(2y – 3)(6y – 1)
500
When 12g of carbon is burned in air, 44g of carbon dioxide is produced. How much carbon is needed to produce 11g of carbon dioxide?
3g
500
A beam is in equilibrium and is supported at each end. It supports a load of 100N at midspan and its self weight is 60N. What is the value of each support reaction? a. 160N b. 80N c. 80kN
b. 80N
500
A child throws a ball vertically upwards with a velocity of 3 m/s. How long does it take for the ball to return to the child? Use s = u x t + 1/2 x a x t x t and g = 10 m/sq second. a. 0.6 seconds b. 1.6 seconds c. 6 seconds
0.6seconds
500
A ball is thrown horizontally from a building at 7m/s and from a height of 20m above the ground. How long does it take for the ball to reach the ground and how far does it travel horizontally? a. 0.2 seconds; 1.4m b. 2 seconds; 14m; c. 20 seconds; 140m Use g = 10 m/sq second and s = u x t + 1/2 x a x t x t vertically and s = u x t horizontally
b. 2 seconds; 14m