Physics
A boy uses a single fixed pulley to lift a load of 50 kgf to some height. Another boy uses a single movable pulley to lift the same load to the same height. The ratio of the two effort is:
- 1:2
- 2:1
- 1:1
- none of these
Related Questions
Which of the following differences between a single fixed pulley and a single movable pulley is incorrect?
Single fixed pulley Single movable pulley (1) It is fixed to a rigid support (i) It is not fixed to a rigid support. (2) The load moves in a direction opposite to the effort. (ii) The load moves in the direction of effort. (3) Its ideal mechanical advantage is 1. (iii) Its ideal mechanical advantage is 1. (4) Its ideal velocity ratio is 2. (iv) Its ideal velocity ratio is 1. (5) The axis of rotation does not move in space. (v) The axis of rotation also moves. - (5)
- (2) and (5)
- (3) and (5)
- (3) and (4)
The relationship between mechanical advantage (M.A.) and velocity ratio (V.R.) for a practical machine is:
- M.A.= V.R.
- M.A.> V.R.
- M.A.< V.R.
- None of these
How many strands are supporting the load in case of block and tackle system of 5 pulleys?
- 4
- 5
- 6
- 7
How many strands are supporting the load in case of block and tackle system of 4 pulleys when effort is in downward direction?
- 5
- 4
- 3
- 6