The diagram shows a wheel with a handle. Two forces, F1 and F2 of equal magnitudes are acting on the handle as shown in the diagram.
(a) Which force produces negative moment?
(b) Is the wheel in equilibrium? (Yes or No)
(c) Justify your answer stated in (b).
(a) Force F1 produces the negative moment because it tends to rotate the wheel clockwise.
(b) No, the wheel is not in equilibrium.
(c) For equilibrium, the sum of clockwise moments must equal the sum of anticlockwise moments about the centre O. Although F1 and F2 have equal magnitudes, their perpendicular distances from the centre are different. Therefore, their moments are not equal and opposite, the net moment is not zero, and the wheel is not in equilibrium.
More ICSE Moderate level questions
Complete the following by choosing the correct answers from the bracket: (a) A car is moving in uniform circular motion. The direction of friction between the tyres and the path is ............... [towards the centre / tangential to the path]. (b) When a ray of light passes from a denser to a rarer medium, its wavelength ............... [decreases / increases]. (c) The lid of a calorimeter minimises heat loss by ............... [convection / radiation]. (d) Quality of sound depends on its ............... [amplitude / waveform]. (e) A substance whose resistance becomes almost negligible at a temperature near absolute zero is called a ............... [semiconductor / superconductor]. (f) ............... radiation deviates minimum in a magnetic field [Alpha / Beta].
For a body to be in dynamic equilibrium: (a) its momentum must be zero (b) its acceleration must be zero (c) its kinetic energy must be zero (d) its velocity must be zero
State two factors on which the position of Center of Gravity of a body depends.
(a) Define Centre of Gravity. (b) A hollow ice cream cone has height 6 cm. (i) Where is the position of its centre of gravity from the broad base? (ii) Will its position change when it is filled completely with honey? Write Yes or No.
A metre scale of weight 50 gf can be balanced at 40 cm mark without any weight suspended on it. (a) If this ruler is cut at its centre then state which part [0 to 50 cm or 50 to 100 cm] of the ruler will weigh more than 25 gf. (b) What minimum weight placed on this metre ruler can balance this ruler when it is pivoted at its centre?
Akash takes a uniform metre scale and suspends a weight of 2 N at one end ‘X’, and a weight of 5 N on the other end ‘Y’. He then balances the ruler horizontally on a knife edge placed at 70 cm from X. Draw a diagram of the arrangement and calculate the weight of the ruler.
A non-uniform kite is hanging freely from the branch of a tree as shown. Study the figure and answer the following: (a) Fill in the blank. ............... [P, Q, R or S] is the most probable position of its centre of gravity. (b) Support your answer to (a) with a reason.
The diagram shows wheel O pivoted at point A. Three equal forces F1, F2 and F3 act at point B on the wheel. (a) Which force will produce maximum moment about A? (b) Give a reason for your answer in (a).
(a) What is the position of centre of gravity of a triangular lamina? (b) When this triangular lamina is suspended freely from any one vertex, what is the moment of force produced by its own weight in its rest position?
Fill in the blanks: (a) A stone tied to a string is rotated in a horizontal plane. The tension in the string provides the __________ force necessary for circular motion. (b) The work done by this force at any instant is __________.
When a bell fixed on a cycle rings, then the energy conversion that takes place is: (a) gravitational potential energy to sound energy (b) kinetic energy to sound energy (c) sound energy to electrical energy (d) sound energy to mechanical energy
A non-uniform beam of weight 120 N pivoted at one end is shown in the diagram below. Calculate the force F required to keep the beam in equilibrium.
