Physics
The diagram below shows a block and tackle system.
(a) Copy and complete the labelled diagram showing the correct connection of the tackle, the direction of the forces involved to obtain maximum V.R. with the convenient direction.
(b) Calculate the M.A. of this pulley system if its efficiency is 80%.
Related Questions
(a) Mixture of red + blue + green is passed through a convex lens as shown in the diagram below. State whether the ray passes through a single point or through different points on principle axis after refraction.
(b) Name the invisible radiations which can be obtained using quartz prism? State one use of these radiations.
(c) Name one radiations having wavelength longer than the wavelength of these radiations.
Sumit and Sachin went for a trek and during the journey they visited a cottage. They suspended their bags to the two ropes hanging from P and Q on a wheel capable of rotating around O. Sumit suspended his bag to the rope Q and Sachin suspended his bag from the rope P. The wheel remained in equilibrium.
(a) State with a reason who is carrying a heavier bag.
(b) Based on the principle of moments, write a mathematical relation that can be used to determine the weight (W) of Sachin's bag, given that the weight of Sumit's bag is 18 kgf.
The figure alongside shows a simple pendulum of mass 200 g. It is displaced from the mean position A to the extreme position B. The potential energy at the position A is zero. At the position B the pendulum bob is raised by 5 m.
(i) What is the potential energy of the pendulum at the position B?
(ii) What is the total mechanical energy at point C?
(iii) What is the speed of the bob at the position A when released from B?
(Take g = 10 ms-2 and there is no loss of energy.)
A person standing in front of a cliff fires a gun and hears its echo after 3s. If the speed of sound in air is 336 ms-1
(a) Calculate the distance of the person from the cliff.
(b) After moving a certain distance from the cliff, he fires the gun again and this time the echo is heard 1.5 s later than the first. Calculate distance moved by the person.