Why are SI units commonly used in engineering?
Because SI units are universal standardisation worldwide
Convert 3.5mm to metres
0.0035m (3.5 x 10^-3m)
Round 0.004987 to 2 s.f.
0.00499
What’s the difference between accuracy and precision?
Accuracy = closeness to the true value
Precision = repeatability
Simply the ratio 12:18
2:3
Increase 80 by 15%
92
If a gear ratio is 4:1, what does that mean?
Driver turns 4 times for 1 turn of the driven gear
Evaluate (2^3)(2^4)
2^7=128
Simplify (x^3)^2
x^6
Solve for x: log10(x) = 2
x = 100
Use laws of logs: log10(AB) =
log10(A) + log10(B)
Factorise x^2 - 9
(x-3)(x+3)
Rearrange for x: y=3x+2
x=(y-2)/3
What does gradient represent physically?
Rate of change (ex. velocity on a displacement-time graph)
Solve: x+y=7 x-y=3
x=5, y=2
Give the formula for the area of a circle
A = πr²
Convert 250cm^3 to m^3
2.5 x 10^-4m^3 (1cm^3 = 1x10^-6m^3)
Write the vector from A(1, 2) to B(5, -1)
(4, -3)
Give the magnitude of v = (3, 4)
5
Give the resultant forces of (4, 0)N and (0, 3)N
(4, 3)N; magnitude 5N
What is the formula that links displacement, initial velocity, acceleration and time
s=ut+1/2at^2
If u = 0, a = 2m/s^2, t = 3s, find s
s=0 + 1/2 x 2.9
s=13.05m
Give the formula for a straight line
y=mx+c
What does the derivative represent physically?
Rate of change / gradient of the curve
