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Pushing a wall/anything that does not move when force is applied.
sharon kalunda answered the question on April 2, 2019 at 11:16
- The graph below shows the variation between force and distance for a boy pushing a concrete block of mass 25kg through a vertically height of...(Solved)
The graph below shows the variation between force and distance for a boy pushing a concrete block of mass 25kg through a vertically height of 12m.
(i) Determine the total work done by the boy within 70m
(ii) How much energy is wasted?
(iii) Give an account for the energy wasted
Date posted: April 2, 2019. Answers (1)
- Figure below shows a wire loop with a string that has been dipped into soap solution.(Solved)
Figure below shows a wire loop with a string that has been dipped into soap solution.
i) Sketch a similar diagram to show the observed effect if the soap film is punctured at X
ii) Explain the observations made in (i) above
Date posted: April 2, 2019. Answers (1)
- The diagram figure below shows a steel ball bearing gently dipped in a viscous liquid contained in a tall cylinder.(Solved)
The diagram figure below shows a steel ball bearing gently dipped in a viscous liquid contained in a tall cylinder.
Name giving their directions the forces acting on the ball bearing as it moves down the cylinder.
Date posted: April 2, 2019. Answers (1)
- State the condition necessary for the law of conservation of linear momentum to hold.(Solved)
State the condition necessary for the law of conservation of linear momentum to hold.
Date posted: April 2, 2019. Answers (1)
- Mercury on a clean glass slide collects into small spherical balls as shown in figure below.
Explain why(Solved)
Mercury on a clean glass slide collects into small spherical balls as shown in figure below.Explain why
Date posted: April 2, 2019. Answers (1)
- The figure below shows two blocks of masses M1=1.5kg and M2 = 2.0kg which are in contact on a frictionless table(Solved)
The figure below shows two blocks of masses M1=1.5kg and M2 = 2.0kg which are in contact on a frictionless table
A force F=7N acts on the bodies, determine the force on mass M2
Date posted: April 2, 2019. Answers (1)
- Give one difference between limiting and dynamic forces of friction(Solved)
Give one difference between limiting and dynamic forces of friction
Date posted: April 2, 2019. Answers (1)
- Explain why it is easier to ride a bicycle round a bend on a road if the surface is dry than when it is wet(Solved)
Explain why it is easier to ride a bicycle round a bend on a road if the surface is dry than
when it is wet
Date posted: April 2, 2019. Answers (1)
- The figure below shows a block of mass 25g and density 200kg/m3 submerged beam by means of a thread. A mass of 2g if suspended...(Solved)
The figure below shows a block of mass 25g and density 200kg/m3 submerged beam by means of a thread. A mass of 2g if suspended form the beam as shown in the figure below.
(i) Determine the up thrust force acting on the block.
(ii) Calculate the density of the liquid.
Date posted: April 2, 2019. Answers (1)
- A bubble of air has a diameter of 2.0 mm when it is 0.5m below the water surface of a boiler.
Calculate the diameter of the...(Solved)
A bubble of air has a diameter of 2.0 mm when it is 0.5m below the water surface of a boiler.
Calculate the diameter of the bubble as it reaches the surface, assuming that the temperature
remains constant.(Take g = 10Nkg-1 density of water = 103kgm-3 and atmospheric pressure = 105Mn-2
Date posted: April 2, 2019. Answers (1)
- A crane lifts a load 500kg through a vertical distance of 4m in 8 seconds. Determine:(Solved)
A crane lifts a load 500kg through a vertical distance of 4m in 8 seconds. Determine:
(i) Work done by the crane
(ii) Power developed by the crane
(iii) Efficiency of the crane given that it is operated by an electric motor rated 2.8Kw
Date posted: April 2, 2019. Answers (1)
- Define work and state its S.I units(Solved)
Define work and state its S.I units
Date posted: April 2, 2019. Answers (1)
- A man uses a block and tackle mechanism of velocity ratio 6 to lift a car engine smoothly through a height of 1 m in...(Solved)
A man uses a block and tackle mechanism of velocity ratio 6 to lift a car engine smoothly through a height of 1 m in 5s. The man applies a force of 300N while the mass of the engine is 120 kg. Determine:
(i) The mechanical advantage of the pulley system.
(ii) its efficiency.
Date posted: April 2, 2019. Answers (1)
- A bicycle has wheels 66 cm in diameter. Its crank wheel has 44 teeth and the rear sprocket 16 teeth. The crank radius is 16.5...(Solved)
A bicycle has wheels 66 cm in diameter. Its crank wheel has 44 teeth and the rear sprocket 16 teeth. The crank radius is 16.5 cm.
(i) Determine the radius of the rear sprocket.
(ii) The bicycle moves when the rear sprocket is made to move. Hence determine the
velocity ratio.
Date posted: April 2, 2019. Answers (1)
- A wheel and axle are used to raise a load of 280N by a force 40N applied to the rim of the
wheel. If the radii...(Solved)
A wheel and axle are used to raise a load of 280N by a force 40N applied to the rim of the
wheel. If the radii of the rim and axle are 70cm and 5cm respectively, calculate:
(i) The mechanical advantage
(ii) The velocity ratio
(iii) The efficiency
Date posted: April 2, 2019. Answers (1)
- The graph below shows the potential energy against displacement for a body of mass 80 g.(Solved)
The graph below shows the potential energy against displacement for a body of mass 80 g.
The body oscillates about point R. Calculate the velocity of the body at:
(i) P and T
(ii) Q and S
(iii) at R
Date posted: April 2, 2019. Answers (1)
- State the law of conservation of energy(Solved)
State the law of conservation of energy
Date posted: April 2, 2019. Answers (1)
- The diagram below shows a charcoal refrigerator. (i) Explain why charcoal is used and why it is sprinkled with water...(Solved)
The diagram below shows a charcoal refrigerator.
(i) Explain why charcoal is used and why it is sprinkled with water
(ii) What is the role of the metallic tank and the wire mesh
Date posted: April 2, 2019. Answers (1)
- Briefly explain two ways other than direct heating by which quantity of liquid may be made to evaporate more quickly(Solved)
Briefly explain two ways other than direct heating by which quantity of liquid may be made to evaporate more quickly
Date posted: April 2, 2019. Answers (1)
- 0.5kg of naphthalene contained in an aluminium can of mass 0.4kg is melted in a water bath and raised to a temperature of 100oC ....(Solved)
0.5kg of naphthalene contained in an aluminium can of mass 0.4kg is melted in a water bath and raised to a temperature of 100oC . Calculate the total heat given out when the can and its contents are allowed to cool to room temperature, 20oC . Neglect losses by evaporation during heating process and give your answer to the nearest kilojoule.(For naphthalene melting point = 80oC , Specific heat capacity for both liquid and solid =2100J/KgK; specific latent heat of fusion = 170000J/Kg.For aluminium: specific heat capacity = 900J/Kg/k
Date posted: April 2, 2019. Answers (1)