Question

In a Roman steelyard, the length of the scale is 1.5 m and the weight of the rider is 20 N. The load is suspended 15 cm away from the point of suspension, then the maximum load that can be measured by it is _________. (Take g = 10 m s^-2)

• A. 20 kg wt
• B. 20 N
• C. 2 N
• D. 2 kg wt

Answer 1

The correct option is A

20 kg wt

Step 1, Given data

Length of the scale = 1.5 m = 150 cm

Weight of the rider = 20 N

Load is suspended 15 cm away from the point of suspension.

Step 2, Finding the maximum load

From the principle of the lever we can write

$Load\times 15=20\times 150$

After solving

Load$=200N=20kgwt$

Hence the correct option is (A).