WAEC - Physics (2001 - No. 14)
A screw jack with a Tommy bar of length 12cm is used to raise a car through a vertical height of 25cm by turning the Tommy bar through 50 revolutions. Calculate the approximate velocity ratio of the jack [\(\pi = 3.142\)]
21
38
48
151
Giải thích
P = \(\frac{25}{50} = 0.5\)
V.R = \(\frac{2\pi D}{p} = \frac{2 \times 3.142 \times 12}{0.5}\)
= 151
V.R = \(\frac{2\pi D}{p} = \frac{2 \times 3.142 \times 12}{0.5}\)
= 151