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X – rays have more penetration power.
X-rays have high frequency/energy.
sharon kalunda answered the question on September 6, 2019 at 07:57
- The following figure shows the path of a ray of light through a transparent material placed in air.(Solved)
The following figure shows the path of a ray of light through a transparent material placed in air.
![pic6920191051.png](/questions/uploads/pic6920191051.png)
Determine the refractive index of the transparent material
Date posted: September 6, 2019. Answers (1)
- The control grid in a cathode ray oscilloscope (CRO) is used to control the brightness of the beam on the screen. Explain how the brightness...(Solved)
The control grid in a cathode ray oscilloscope (CRO) is used to control the brightness of the beam on the screen. Explain how the brightness of the beam can be increased.
Date posted: September 6, 2019. Answers (1)
- A current of 0.7A flows through a wire when a potential difference of 0.35V is applied at the ends of the wire. If the wire...(Solved)
A current of 0.7A flows through a wire when a potential difference of 0.35V is applied at the ends of the wire. If the wire is 0.5m long and has a cross-sectional area of 8.0 x 103mm2, determine its resistivity.
Date posted: September 6, 2019. Answers (1)
- The figure below shows a positively charged metal plate with an earthing connection. State and explain the final charge of the plate.(Solved)
The figure below shows a positively charged metal plate with an earthing connection. State and explain the final charge of the plate.
![pic6920191035.png](/questions/uploads/pic6920191035.png)
Date posted: September 6, 2019. Answers (1)
- The figure below shows a load of 50N being raised by pulling it along an inclined plane of length 2.0m.(Solved)
The figure below shows a load of 50N being raised by pulling it along an inclined plane of length 2.0m.
![pic6920191026.png](/questions/uploads/pic6920191026.png)
Determine
i. The work done by the 22N force
ii. The work done against the load
iii. The efficiency of the system
Date posted: September 6, 2019. Answers (1)
- The figure below shows a buoy of capacity 40 litres and mass 10kg. It is held in position in sea water of
density 1.04g/cm3 by a...(Solved)
The figure below shows a buoy of capacity 40 litres and mass 10kg. It is held in position in sea water of
density 1.04g/cm3 by a light cable fixed to the bottom so that ¾ of its volume is below the water surface.
![pic6920191021.png](/questions/uploads/pic6920191021.png)
Determine the tension in the cable.
Date posted: September 6, 2019. Answers (1)
- The figure below shows a block with a graduated side and dimensions 4cm by 16cm, just about to be lowered
into a liquid in an overflow...(Solved)
The figure below shows a block with a graduated side and dimensions 4cm by 16cm, just about to be lowered
into a liquid in an overflow can.
![pic6920191009.png](/questions/uploads/pic6920191009.png)
During an experiment with this set-up, the following was recorded:
- The block floated with three-quarter of it submerged.
- Initial reading of balance = 0g
- Final reading of balance = 154g
Use the information to determine the density of
(i) the block
(ii) the liquid
Date posted: September 6, 2019. Answers (1)
- A bicycle wheel makes 300 revolutions per minute. Calculate the angular velocity of the wheel.(Solved)
A bicycle wheel makes 300 revolutions per minute. Calculate the angular velocity of the wheel.
Date posted: September 6, 2019. Answers (1)
- The figure below shows two masses 0.1kg and 2kg connected by a string through a hole on a smooth horizontal surface.The 0.1kg rotates in a...(Solved)
The figure below shows two masses 0.1kg and 2kg connected by a string through a hole on a smooth horizontal surface.
![pic692019948.png](/questions/uploads/pic692019948.png)
The 0.1kg rotates in a horizontal circle of radius 3cm. Calculate the angular velocity of the 0.1kg mass, when the system is in equilibrium.
Date posted: September 6, 2019. Answers (1)
- Three insoluble powders A, B and C of densities dA, dB and dC, such that dA>dB>dC, are mixed and put into a container.The container is...(Solved)
Three insoluble powders A, B and C of densities dA, dB and dC, such that dA>dB>dC, are mixed and put into a container.The container is then whirled in a horizontal circle as shown in the figure below.
![pic692019931.png](/questions/uploads/pic692019931.png)
(i) Label on the figure, the positions of the powders after some time.
(ii) Give a reason for your answer in (i)
Date posted: September 6, 2019. Answers (1)
- A ball slides off a horizontal table 4m high with a velocity of 12m/s, find;
(i) the time it takes to hit the floor. (g =...(Solved)
A ball slides off a horizontal table 4m high with a velocity of 12m/s, find;
(i) the time it takes to hit the floor. (g = 10ms-2)
(ii) the range
Date posted: September 6, 2019. Answers (1)
- A car decelerates uniformly from a velocity of 20m/s to rest in 4 seconds. It takes 4 seconds to reverse with uniform acceleration to its...(Solved)
A car decelerates uniformly from a velocity of 20m/s to rest in 4 seconds. It takes 4 seconds to reverse with uniform acceleration to its original starting point.
(i) Sketch a velocity time graph for the motion of the car.
(ii) Use your sketch in c (i) to determine the total displacement of the car.
Date posted: September 6, 2019. Answers (1)
- The figure below shows the displacement – time graph of the motion of a particle.
State the nature of the motion of the particle between?
(i)...(Solved)
The figure below shows the displacement – time graph of the motion of a particle.
![pic692019908.png](/questions/uploads/pic692019908.png)
State the nature of the motion of the particle between?
(i) AB
(ii) BC
(iii CD
Date posted: September 6, 2019. Answers (1)
- State the physical quantity represented by the gradient of a displacement – time graph(Solved)
State the physical quantity represented by the gradient of a displacement – time graph
Date posted: September 6, 2019. Answers (1)
- A substance of mass 2kg and specific heat capacity 400J/kg/k initially at 800C is immersed in water at 190C. If the final temperature of the...(Solved)
A substance of mass 2kg and specific heat capacity 400J/kg/k initially at 800C is immersed in water at 190C. If the final temperature of the mixture is 200C. Calculate the mass of water. (Specific heat capacity of water = 4200J/kg/k)
Date posted: September 6, 2019. Answers (1)
- A force of 20N is used to stretch a spring through 5cm. Calculate the elastic potential energy stored in the spring.(Solved)
A force of 20N is used to stretch a spring through 5cm. Calculate the elastic potential energy stored in the spring.
Date posted: September 6, 2019. Answers (1)
- A pipe of radius 3mm is connected to another pipe of radius 9mm. If water flows in the water pipe at a speed of 2m/s,...(Solved)
A pipe of radius 3mm is connected to another pipe of radius 9mm. If water flows in the water pipe at a speed of 2m/s, what is the speed in the narrower pipe?
Date posted: September 6, 2019. Answers (1)
- A uniform 120m metal rod is pivoted near one of its ends and kept in equilibrium by a spring balance as shown in the figure...(Solved)
A uniform 120m metal rod is pivoted near one of its ends and kept in equilibrium by a spring balance as shown in the figure below.
![pic692019834.png](/questions/uploads/pic692019834.png)
The reading indicated by the spring balance is 2.0N. Work out the mass of the metal rod. (g = 10N/kg)
Date posted: September 6, 2019. Answers (1)
- The spiral springs shown in the figure below are identical. Each spring has a constant K = 300N/m.
Determine the extension caused by the 150N weight...(Solved)
The spiral springs shown in the figure below are identical. Each spring has a constant K = 300N/m.
![pic692019828.png](/questions/uploads/pic692019828.png)
Determine the extension caused by the 150N weight (Ignore weight of springs and connecting rods)
Date posted: September 6, 2019. Answers (1)
- A micrometer screw gauge has a zero error of -0.02mm. It is used to measure the diameter of a wire. If the actual diameter of...(Solved)
A micrometer screw gauge has a zero error of -0.02mm. It is used to measure the diameter of a wire. If the actual diameter of the wire is 0.28mm. Draw the micrometer screw gauge showing the diameter of the wire.
Date posted: September 6, 2019. Answers (1)