Get premium membership and access questions with answers, video lessons as well as revision papers.
This is due to Fitzgerald-lorentz contraction (length- contraction) When observer is traveling with speed approaching c, and then he measure x1 first, as he goes ahead to measure x2 the rocket will have moved at time t past the rod and therefore the length will have contracted.
Nolana answered the question on March 29, 2019 at 06:37
- .... Three resistors of resistance 2.0 ohms, 4.0 ohms and 6.0 ohms are connected together in a circuit.(Solved)
Three resistors of resistance 2.0 Ω, 4.0 Ω and 6.0 Ω are connected together in a circuit.
Draw a circuit diagram to show the arrangement of the resistor which Gives:
(i) Effective resistance of 3.0 Ω
(ii) Minimum resistance
Date posted: March 27, 2019. Answers (1)
- Three resistors of resistance 2.0 O, 4.0 O and 6.0 O are connected together in a circuit.(Solved)
Three resistors of resistance 2.0 Ω, 4.0 Ω and 6.0 Ω are connected together in a circuit.
Draw a circuit diagram to show the arrangement of the resistor which Gives
(i) Effective resistance of 3.0 Ω
(ii) Minimum resistance
Date posted: March 27, 2019. Answers (1)
- A narrow beam of electrons in a cathode ray oscilloscope (CRO) strike the screen producing a spot. State what is observed on the screen if...(Solved)
A narrow beam of electrons in a cathode ray oscilloscope (CRO) strike the screen producing a spot. State what is observed on the screen if a low frequency a.c source is connected across the y-input of the CRO
Date posted: March 27, 2019. Answers (1)
- Figure below shows wavefronts approaching the boundary between two media.(Solved)
Figure below shows wavefronts approaching the boundary between two media.
The speed of the waves in medium (2) is higher than that in medium (1). On the same diagram complete the figure to show the wavefronts after crossing the boundary.
Date posted: March 27, 2019. Answers (1)
- Figure below shows a hack-saw blade clamped horizontally on a bench and the free end is made to vibrate about the rest position.(Solved)
Figure below shows a hack-saw blade clamped horizontally on a bench and the free end is made to vibrate about the rest position.
Determine the frequency of vibration of the blade.
Date posted: March 27, 2019. Answers (1)
- The diagram in figure below shows an object O placed in front of a converging lens. F and F are the principal focal for the...(Solved)
The diagram in figure below shows an object O placed in front of a converging lens. F and F are the principal focal for the lens.
The object is now moved along the principal axis until a virtual image is produced.
On the same diagram: Sketch rays to show formation of the virtual image
Date posted: March 27, 2019. Answers (1)
- You are provided with the following; A cell and holder, a switch, a rheostat, an ammeter, a voltmeter and connecting wires. Draw a diagram for...(Solved)
You are provided with the following; A cell and holder, a switch, a rheostat, an ammeter, a voltmeter and connecting wires. Draw a diagram for a circuit that could be used to investigate the variation of the potential difference across the cell with the current drawn from the cell.
Date posted: March 27, 2019. Answers (1)
- Figure below shows three point sources of light with an opaque object placed between them and the screen.(Solved)
Figure below shows three point sources of light with an opaque object placed between them and the screen.
Explain the nature of the shadow formed along B and C.
Date posted: March 27, 2019. Answers (1)
- The strip placed n a pivot and kept in equilibrium by forces as shown in figure below(Solved)
The strip placed n a pivot and kept in equilibrium by forces as shown in figure below
(i) Determine the value of F and R
(ii) X is the distance from the end of the plank to the point of application of force F. Force F is now applied at various points nearer to the pivot so that x increases. Equilibrium is maintained all the time. On the axes provided sketch the relation between force F and x.
(iii) Give a reason for the answer in (ii) above
Date posted: March 27, 2019. Answers (1)
- A machine of velocity ratio 45, overcomes a load of 4.5 x 103N when an effort of 135N is applied.(Solved)
A machine of velocity ratio 45, overcomes a load of 4.5 x 103N when an effort of 135N is applied.
Determine:
(i) The mechanical advantage of the machine
(ii) Efficiency of the machine
(iii) The percentage of the work that goes to waste.
Date posted: March 27, 2019. Answers (1)
- Figure below shows part of a hydraulic press. The plunger is the position where effort is applied while the Ram piston is the position where...(Solved)
Figure below shows part of a hydraulic press. The plunger is the position where effort is applied while the Ram piston is the position where load is applied. The plunger has cross-section area, a m2 while the Ram piston has cross section area, a m2.
When the plunger moves down a distance d the Ram piston moves up a distance D.
(i) State the property of liquid pressure on which the working of the hydraulic press works.
(ii) Derive an impression for the velocity ratio (V.R) in terms of A and a.
Date posted: March 27, 2019. Answers (1)
- A sealed gas cylinder contains 300cm3 of certain gas at a temperature of 250C, and at a pressure of 9.5x 104pa. the gas in the...(Solved)
A sealed gas cylinder contains 300cm3 of certain gas at a temperature of 250C, and at a pressure of 9.5x 104pa. the gas in the cylinder was then cooled to 100C. Determine the new pressure of the gas in the cylinder.
Date posted: March 27, 2019. Answers (1)
- A block of metal of mass 150g at 1000C is dropped into a lagged calorimeter of heat capacity 40JK-1 containing 100g of water at 250C....(Solved)
A block of metal of mass 150g at 1000C is dropped into a lagged calorimeter of heat capacity 40JK-1 containing 100g of water at 250C. The temperature of the resulting mixture is 340C. (Specific heat capacity of water=4200JK-1).
Determine:
(i) Heat gained by calorimeter;
(ii) Heat gained by water;
(iii) Heat lost by the metal block;
(iv) Specific heat capacity of the metal block
Date posted: March 27, 2019. Answers (1)
- Figure below shows a toy resting on top of a closed bottle. Use the information on the figure to answer questions below(Solved)
Figure below shows a toy resting on top of a closed bottle. Use the information on the figure to answer questions below
a) Mark on the diagram, point Q, the approximate centre of gravity of the toy.
b) Giving a reason, name the state of equilibrium of the toy.
Date posted: March 27, 2019. Answers (1)
- Water is known to boil at 1000C. A student heated some water and noticed that it boiled at 1010C.
State two possible reasons for this observation(Solved)
Water is known to boil at 1000C. A student heated some water and noticed that it boiled at 1010C.
State two possible reasons for this observation
Date posted: March 27, 2019. Answers (1)
- Figure below shows a brick placed on a plane inclined at an angle ? to the horizontal. The weight, W, of the brick is shown.(Solved)
Figure below shows a brick placed on a plane inclined at an angle θ to the horizontal. The weight, W, of the brick is shown.
a) On the same diagram show with arrows the other two forces acting on the brick and name them.
b) State how each of the two forces named (a) above is affected when the angle θ is reduced.
Date posted: March 27, 2019. Answers (1)
- The masses of equal volumes of a certain liquid and of water were found to be mv and mw respectively. Given that the density of...(Solved)
The masses of equal volumes of a certain liquid and of water were found to be mv and mw respectively. Given that the density of water is 1gcm-3, express the density, p, of the liquid in terms of mv mw (show your work)
Date posted: March 27, 2019. Answers (1)
- The diagram below shows a rectifier circuit for an alternating current (a.c) input.(Solved)
The diagram below shows a rectifier circuit for an alternating current (a.c) input.
Draw the traces of the signal obtained on CRO connected across QS and PR.
Date posted: March 27, 2019. Answers (1)
- You are provided with a diode, a resisitor R, an a.c source of low voltage and connecting wires. In the space provided, sketch the circuit...(Solved)
You are provided with a diode, a resisitor R, an a.c source of low voltage and connecting wires. In the space provided, sketch the circuit diagram for a half-wave rectifier and indicate the terminals where the output voltage v0 may be connected.
Date posted: March 27, 2019. Answers (1)
- Using the components symbols shown in the fig, sketch a series circuit diagram for a forward biased diode.(Solved)
Using the components symbols shown in the fig, sketch a series circuit diagram for a forward biased diode.
Date posted: March 27, 2019. Answers (1)