- A rocket propelled upward with a constant thrust. Assuming friction due to air is negligible and the burning of the fuel is steady. Explain its...(Solved)
A rocket propelled upward with a constant thrust. Assuming friction due to air is negligible and the burning of the fuel is steady. Explain its motion.
Date posted: March 26, 2019. Answers (1)
- Figure below shows a cell of Emf E volts and internal resistance r ohms. Connected to an external resistor R. If the current flowing is...(Solved)
Figure below shows a cell of Emf E volts and internal resistance r ohms. Connected to an external resistor R. If the current flowing is 0.5A, find and expression for the internal resistance r.
Date posted: March 26, 2019. Answers (1)
- Two masses of 3kg and 7kg are connected by a light string. The 3 kg mass rests on a smooth incline plane 300 to the...(Solved)
Two masses of 3kg and 7kg are connected by a light string. The 3kg mass rests on a smooth incline plane 300 to the horizontal. The 7kg mass hangs freely from the friction-less pulley attached to the top of plane.
i) Draw a diagram showing the bodies and identify the forces acting on the 3 kg mass.
ii) Calculate the acceleration of the masses.
Date posted: March 26, 2019. Answers (1)
- A student was investigating the brightness of bulbs when set up in different circuits. He used identical bulbs and cells.He set up circuits A and...(Solved)
A student was investigating the brightness of bulbs when set up in different circuits. He used identical bulbs and cells.He set up circuits A and B as shown in figure (A) and (B) below.
State and explain which set up had the bulbs light brightest.
Date posted: March 26, 2019. Answers (1)
- A positively charged material was brought close to an insulated metallic object as shown in figure below. Show the distribution of charge in the object.(Solved)
A positively charged material was brought close to an insulated metallic object as shown in figure below. Show the distribution of charge in the object.
Date posted: March 26, 2019. Answers (1)
- A boy scout standing a distance x from a tall building blows a whistle and hears its echo 1.7 seconds later. Determine the
distance X between...(Solved)
A boy scout standing a distance x from a tall building blows a whistle and hears its echo 1.7 seconds later. Determine the
distance X between the boy and the wall given that the speed of sound in air is 340m/s.
Date posted: March 26, 2019. Answers (1)
- Figure below represents an object O and its image I after reflection by a convex mirror. On the same diagram locate by construction the principal...(Solved)
Figure below represents an object O and its image I after reflection by a convex mirror. On the same diagram locate by construction the principal focus F of the mirror.
Date posted: March 26, 2019. Answers (1)
- Water waves have a speed of 24cm/s in the deep water. Consecutive waves crests are 0.08m apart in the deep water.calculate the frequency of the...(Solved)
Water waves have a speed of 24cm/s in the deep water. Consecutive waves crests are 0.08m apart in the deep water.calculate the frequency of the source producing the wave.
Date posted: March 26, 2019. Answers (1)
- Plane water waves produced in a ripple tank are passed from a region of deep water into a region of shallow water. Figure below shows...(Solved)
Plane water waves produced in a ripple tank are passed from a region of deep water into a region of shallow water. Figure below shows the top view of the tank.
State what happens at the boundary to the frequency of the waves.
Date posted: March 26, 2019. Answers (1)
- A ray of light is incident on a plane mirror as shown in figure below.(Solved)
A ray of light is incident on a plane mirror as shown in figure below.
Determine the angle of reflection.
Date posted: March 26, 2019. Answers (1)
- State a factor that determines the angle at which a road should be banked at a bend.(Solved)
State a factor that determines the angle at which a road should be banked at a bend.
Date posted: March 26, 2019. Answers (1)
- A stone of mass 200g tied to a long string 1m long and whirled round in a vertical circle at an angular speed of 6.28...(Solved)
A stone of mass 200g tied to a long string 1m long and whirled round in a vertical circle at an angular speed of 6.28 rad/s.
i) Why is the stone said to be accelerating.
ii) Determine the linear velocity.
iii) Its periodic time.
iv) The critical speed of the stone if it is to describe a vertical circle.
Date posted: March 26, 2019. Answers (1)
- Figure below shows a small mass being rotated in a horizontal circle through a plastic tube. It is observed that as the small moves is...(Solved)
Figure below shows a small mass being rotated in a horizontal circle through a plastic tube. It is observed that as the small moves is rotated at constant speed, the heavy mass remains at the same horizontal level.
i) State one adjustment that can be done to make the heavy mass move upwards.
ii) State the effect on the small mass if a heavier mass was used in place of the one above and the radius of rotation remains constants.
Date posted: March 26, 2019. Answers (1)
- A mass is projected horizontally from height of 5m above the ground with a velocity of 30m/s. Calculate:(Solved)
A mass is projected horizontally from height of 5m above the ground with a velocity of 30m/s. Calculate:
a) The time taken to reach the ground
b) The horizontal distance traveled before hitting the ground
c) The vertical velocity with which the mass hits the ground
Date posted: March 26, 2019. Answers (1)
- Figure below shows a block of dimensions 2cm × 4cm × 12cm floating in a liquid of density 1250kg/m³(Solved)
Figure below shows a block of dimensions 2cm × 4cm × 12cm floating in a liquid of density 1250kg/m³
Find
i) The upthrust on the block.
ii) The weight of the block.
iii) The force needed to just submerge the block completely.
Date posted: March 26, 2019. Answers (1)
- A particle initially at A moves along an arc AB of a horizontal circle of radius 4m and centre O.A is south of O and...(Solved)
A particle initially at A moves along an arc AB of a horizontal circle of radius 4m and centre O.A is south of O and angle AOB is 600. Determine the displacement AB.
Date posted: March 26, 2019. Answers (1)
- Figure below shows a test tube floating in water in a tall beaker.(Solved)
Figure below shows a test tube floating in water in a tall beaker.
i) State what can be done to make the text tube floating vertically upright.
ii) Explain how the test tube may be calibrated to measure relative densities of liquids.
iii) State what can be done to increase the sensitivity of such an instrument.
Date posted: March 26, 2019. Answers (1)
- A block slides off a horizontal table 4 meters high with a velocity of 12-m/s. Find:
a) The horizontal distance from the table at which the...(Solved)
A block slides off a horizontal table 4 meters high with a velocity of 12-m/s. Find:
a) The horizontal distance from the table at which the block hits the floor.
b) The horizontal and vertical components of the velocity when it reaches the floor.
Date posted: March 26, 2019. Answers (1)
- An object is projected vertically upwards at a speed of 15m/s. How long will it take to return to the same level of projection?(Solved)
An object is projected vertically upwards at a speed of 15m/s. How long will it take to return to the same level of projection?
Date posted: March 26, 2019. Answers (1)
- Calculate the acceleration shown by the tickers-tape that was made using a ticker timer vibrating at 50HZ.(Solved)
Calculate the acceleration shown by the tickers-tape that was made using a ticker timer vibrating at 50HZ.
Date posted: March 26, 2019. Answers (1)