The diagram shows a uniform meter rule AB which balances horizontally at the 90cm mark when a mass of 0.2kg is suspended from B. Calculate the mass of the meter rule.
A.
0.05kg
B.
0.20kg
C.
0.80kg
D.
1.00kg
Correct answer is A
M\(_r\)(90 - 50) = 0.2(100 - 90)
40M\(_r\) = 0.2 × 10
| M\(_r\) | = | 2
40 |
= | 0.05kg |