help in physics....?

Question

I had a quiz today and I didn't went to school for like a week and I had to answer these two problems, but I really didn't know what to do.I would like someone to explain it to me step by step how to solve it plzzz.

1)A vector drawn 6cm long represent a force of 23N.
what force does a vector that is 13cm long,drawn to the same scale, represent? answer in units of N.

2)A vector drawn 6cm long represents a force of 64N.
How long would you draw a vector for a force of 124N? Answer in units of cm.

Answer 1

Hello LUV -

I assume you understand algebra.

The length of the vector represents the magnitude of the force. So the ratio between the two vector lengths = the ratio between the two forces. Therefore, if 6 cm represents 23N, then 6cm/13cm = 23N/?N or (13cm x 23N)/6cm = ?N

In the same sense, the ratio between the two forces must equal the ratio between the vector lengths. So 64N/124N = 6cm/?cm or 124 x 6 = 64 x ? or 124 x 6 / 64 = ? cm.

Hope this helps.