What size force must be applied to the end of a spanner, given the dimensions as shown in Fig 4.18, in order to reach this torque?
How much less force would be required if a tube of length 96 cm was slid over the spanner? (12)
(c) Define pressure. (6) Is pressure a vector quantity or a scalar quantity? Justify your answer. State Boyle’s law.
4 cm Fig 4.18
(6) (7)
The Seawolf class submarine is the most modern American nuclear submarine. Its hull can withstand pressures of up to 7.154 106 P a; the depth of water that provides this amount of pressure is called its ‘crush depth’. Calculate this depth.
(Acceleration due to gravity 9.8 m s2; density of water 1.0 103 kg m3.) (9)
20 cm
Seawolf class submarine (d) State Archimedes’ principle.
Weather balloons are released regularly into the atmosphere and carry equipment to monitor atmos- pheric conditions.A weather balloon made from a material of mass 10 kg is inflated by filling it with hydrogen gas. The total volume of the inflated balloon is 25 m3.
(i) Calculate the upthrust on the inflated balloon.
(ii) Assuming the volume of the hydrogen is the same as the volume of the balloon, calculate the total weight of the inflated balloon.
(iii) What is the maximum load that the balloon can carry? (9)
(9) (4)
(Density of air 1.25 kg m3, density of hydrogen 0.12 kg m3, acceleration due to gravity 9.8 m s2.)
