122 SECONDARY PHYSICS
11. The figure below shows a U-tube filled with water, mercury
another liquid:
Water
PA
Liquid
22 cm
25 cm
Mercury
(a) Determine the density of the liquid.
(b) State a possible reason why mercury is used.

Suppose you use a machine that gives you a mechanical advantage of 2 to achieve an output force of 30newtons what must the input force be

Three point charges, two positive and one negative, each having a magnitude of 20 μc are placed at the vertices of an equilateral triangle (30 cm on a side). what is the magnitude of the electrostatic force on the negative charge

Jackson is designing a new heater, and he wants to experiment with different thermally conductive materials. which of these materials would be useful in conducting heat?