(a) backstroke
As a valve. Pump handle is drawn out as shown. Volume of air below washer
increases and pressure is reduced below atm. pressure. Air from outside the
pump is drawn in.
(b) forward stroke
As a piston.
Pump handle is pushed in air, the barrel is compressed.
Or
The pressure of compressed air is greater than the air in the tyre.
Kavungya answered the question on June 4, 2019 at 07:28
-
A smooth wooden plane is inclined at an angle of 300 to the horizontal as shown in Figure 5 below. An object of mass 10kg...
(Solved)
A smooth wooden plane is inclined at an angle of 300 to the horizontal as shown in Figure 5 below. An object of mass 10kg is pulled steadily up the plane by a force of 60N. Determine;
(a) the velocity ratio of the inclined plane.
(b) efficiency of the system.
Date posted:
June 4, 2019
.
Answers (1)
-
An immersion heater consumes a voltage of 240V and a current of 10A. If it is used to heat 5kg of water at 200C, find...
(Solved)
An immersion heater consumes a voltage of 240V and a current of 10A. If it is used to heat 5kg of water at 200C, find the final temperature of water after 7 minutes. (Take the specific heat capacity of water = 4200 J/kgk)
Date posted:
June 4, 2019
.
Answers (1)
-
A student observed some pollen grains on the surface of water in a beaker with the
help of hand lens as shown below.
(a) State the observation...
(Solved)
A student observed some pollen grains on the surface of water in a beaker with the
help of hand lens as shown below.
(a) State the observation made.
(b) Explain the observation in (a) above.
(c) What conclusion can be drawn from the above experiment.
Date posted:
June 4, 2019
.
Answers (1)
-
The figure below shows a ray of light incident at an angle of 35.60 at point D on the first face of a glass prism...
(Solved)
The figure below shows a ray of light incident at an angle of 35.60 at point D on the first face of a glass prism ABC. The refractive index of the prism is 1.6.
(i) Determine the angle of refraction at point D.
(ii) Find the angle of incidence of the refracted ray on the face AC to 1 decimal point.
(iii) Complete the ray diagram to show the emergent ray from the face AC.
(iv) State two conditions necessary for total internal reflection to occur.
Date posted:
June 3, 2019
.
Answers (1)
-
An object of height 10.5cm stands before a diverging lens of focal length 20cm and a distance of 10cm from the lens. Determine;
(i) image distance....
(Solved)
An object of height 10.5cm stands before a diverging lens of focal length 20cm and a distance of 10cm from the lens. Determine;
(i) image distance.
(ii) height of the image.
(iii) magnification.
Date posted:
June 3, 2019
.
Answers (1)
-
The graph below show stopping potential Vs against frequency f. (Take C = 3.0 x 108ms¯¹).
Use the graph to determine:-
(i) the threshold wavelength.
(ii) Planck’s...
(Solved)
The graph below show stopping potential Vs against frequency f. (Take C = 3.0 x 108msˉ¹).
Use the graph to determine:-
(i) the threshold wavelength.
(ii) Planck’s constant.
(iii) the work function of the metal.
Date posted:
June 3, 2019
.
Answers (1)
-
The diagram below shows a simplified hydraulic braking system of a car.
(i) State the property of the liquid (oil) that makes its more suitable than...
(Solved)
The diagram below shows a simplified hydraulic braking system of a car.
(i) State the property of the liquid (oil) that makes its more suitable than a gas for use as a brake fluid.
(ii) Explain how the system works starting from when the driver presses the foot pedal.
Date posted:
June 3, 2019
.
Answers (1)
-
Explain how a person is able to draw milk from a glass using a straw.
(Solved)
Explain how a person is able to draw milk from a glass using a straw.
Date posted:
June 3, 2019
.
Answers (1)
-
The following figure shows a wheel and axle used to raise a load W by applying an effort F. The radius of the larger wheel...
(Solved)
The following figure shows a wheel and axle used to raise a load W by applying an effort F. The radius of the larger wheel is R and the small wheel is y.
Given that v = 5cm and R is 8cm, determine the effort required to raise a load of 20N if the efficiency of the system is 80%.
Date posted:
June 3, 2019
.
Answers (1)
-
An immersion heater takes 30 minutes to heat 20kg of water from 250C to 600C. How long would the same heater take to heat the...
(Solved)
An immersion heater takes 30 minutes to heat 20kg of water from 250C to 600C. How long would the same heater take to heat the same mass of kerosene through the same temperature range. (Assume no heat is lost to the surrounding).
Specific heat capacity of water = 4200JKgˉ¹Kˉ¹
Specific heat capacity of kerosene = 2200JKgˉ¹Kˉ¹
Date posted:
June 3, 2019
.
Answers (1)
-
A ball of mass 100g is dropped from a height of 1.25m above the ground surface.
It rebounds to a height of 1.1m. Calculate
(i) velocity of...
(Solved)
A ball of mass 100g is dropped from a height of 1.25m above the ground surface.
It rebounds to a height of 1.1m. Calculate
(i) velocity of the ball before impact.
(ii) force of impact if the ball is in contact with the surface for 0.2S (g = 10N/kg).
Date posted:
June 3, 2019
.
Answers (1)
-
The figure below shows a set-up that can be used to verify Charles law of gases.
(i) State the measurements that should be taken in the...
(Solved)
The figure below shows a set-up that can be used to verify Charles law of gases.
(i) State the measurements that should be taken in the experiment.
(ii) Explain how the measurements taken in (i) above can be used to verify Charles law.
Date posted:
June 3, 2019
.
Answers (1)
-
The diagram below shows an empty wine glass.
(a) State the effect on its stability when wine is put into the glass.
(b) Explain your answer in...
(Solved)
The diagram below shows an empty wine glass.
(a) State the effect on its stability when wine is put into the glass.
(b) Explain your answer in (a) above.
Date posted:
June 3, 2019
.
Answers (1)
-
The graph below shows stopping potential V against frequency for a photocell.
From the graph determine:
(i) Threshold frequency
(ii) Planck’s constant
(iii) Work function of the metal...
(Solved)
The graph below shows stopping potential V against frequency for a photocell.
From the graph determine:
(i) Threshold frequency
(ii) Planck’s constant
(iii) Work function of the metal
(Takee = 1.6 x 10-19c)
Date posted:
June 3, 2019
.
Answers (1)
-
A student designed a transformer to provide power to an electric bell marked 24W, 6V from a 240V mains. He wound 50 turns and N...
(Solved)
A student designed a transformer to provide power to an electric bell marked 24W, 6V from a 240V mains. He wound 50 turns and N turns on an iron ring. When he a connected the coil of 50 turns to the bell and the N turns coil to an a.c, he found that the transformer was only 60% efficient. Find:
(i) The value of N
(ii) The power in the coil with N turns
Date posted:
June 3, 2019
.
Answers (1)
-
The figure below shows a set up by a student.
State and explain what happens to the sound from the buzzer as the bottle and its...
(Solved)
The figure below shows a set up by a student.
State and explain what happens to the sound from the buzzer as the bottle and its contents are cooled to 0oC
Date posted:
June 3, 2019
.
Answers (1)
-
A bullet of mass 20g moving at 400 m/s strikes a block of wood of mass 3.5kg initially at rest. The bullet sticks into the...
(Solved)
A bullet of mass 20g moving at 400 m/s strikes a block of wood of mass 3.5kg initially at rest. The bullet sticks into the block and the two move off together on a horizontal surface, where a frictional retarting force of 4N is acting between the block and surface.
(i) Determine the initial common velocity of bullet and wooden block.
(ii) What distance does the block move before coming to rest?
Date posted:
June 3, 2019
.
Answers (1)
-
A striker kicks a ball of mass 250g initially at rest with a force of 75N. if the foot was in contact with the ball...
(Solved)
A striker kicks a ball of mass 250g initially at rest with a force of 75N. if the foot was in contact with the ball for 0.10sec. Calculate the take off velocity of the ball.
Date posted:
June 3, 2019
.
Answers (1)
-
A test tube of mass 10g and uniform cross-sectional area 4cm2 is partly filled with lead shots and floats vertically in water with 5cm of...
(Solved)
A test tube of mass 10g and uniform cross-sectional area 4cm2 is partly filled with lead shots and floats vertically in water with 5cm of its length submerged.
Find the:-
(i) Mass of the lead shots.
(ii) Length of the test tube that would be submerged in a liquid of density 0.75g/cm3.
Date posted:
June 3, 2019
.
Answers (1)
-
The effort piston of a hydraulic machine is of radius 2.8 cm, while that of the load piston is of radius 14cm. The machine raises...
(Solved)
The effort piston of a hydraulic machine is of radius 2.8 cm, while that of the load piston is of radius 14cm. The machine raises a load of 120 kg at a constant velocity through 2.5m. If the machine has an efficiency of 80%, find:-
(i) the velocity ratio of the hydraulic machine.
(ii) The mechanical advantage of the hydraulic machine.
(iii) The effort needed to raise the load.
Date posted:
June 3, 2019
.
Answers (1)