Question 4 In the following questions the symbols s and a represent displacement and acceleration respectively. The symbols u and v respresent velocities. a) Show that when s is made the subject of the formula v? = u + 2as, then s = - b) Substitute and simplify units within the formula s = 2 - to check that the left and right hand sides are consistent (i.e. in this case the units are both metres, m) Question 6 The displacement s of an object undergoing constant acceleration along a straight line can be calculated from the equation s = ut + satz where u is the object's initial velocity, a is its acceleration and t is the time taken Substitute the following values and units of u, a and t into the above formula to find the corresponding value of s and its unit u = 2.0 m s , a = 4.0 ms' and t = 2.4 s. Question 7 When a force F acts perpendicularly to a surface of area A it exerts a pressure P defined as P F A where F is measured in N A is measured in m The pressure exerted by a liquid depends upon the depth of the liquid according to the equation P = pgh where p is the density of the liquid in kg m-3, g is the gravitational field strength in N kg h is the depth of the liquid in m. Show that the units of the left hand side and right hand side of the following equation are consistent A = pgh