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Negative charge
johnmulu answered the question on February 7, 2017 at 07:21
- A leaf electroscope A is charged and placed on the bench. Another uncharged leaf electroscope B is placed on the same bench and moved close to A until the caps touch(Solved)
A leaf electroscope A is charged and placed on the bench. Another uncharged leaf electroscope B is placed on the same bench and moved close to A until the caps touch. State and explain what is observed on the leaves of A and B.
Date posted: February 7, 2017. Answers (1)
- A positively charged rod is brought near the cap of a leaf electroscope. The cap is the earthed momentarily by touching with the finger(Solved)
A positively charged rod is brought near the cap of a leaf electroscope. The cap is the earthed momentarily by touching with the finger. Finally the rod is withdrawn. The electroscope is found to be negatively charged. Explain how this charge is acquired.
Date posted: February 7, 2017. Answers (1)
- A highly negatively charged rod is gradually brought close to the cap of a positively charged electroscope(Solved)
A highly negatively charged rod is gradually brought close to the cap of a positively charged electroscope. It is observed that the leaf collapses initially and then diverges. Explain the observation.
Date posted: February 7, 2017. Answers (1)
- State the law of electrostatic charges(Solved)
State the law of electrostatic charges
Date posted: February 7, 2017. Answers (1)
- You are provided with a charged electroscope, an insulator and a conductor. Describe how you would use these apparatus to distinguish the insulator from the conductor(Solved)
You are provided with a charged electroscope, an insulator and a conductor. Describe how you would use these apparatus to distinguish the insulator from the conductor.
Date posted: February 7, 2017. Answers (1)
- State the reason why a convex mirror is preferred over a plane mirror for use as driving mirror(Solved)
State the reason why a convex mirror is preferred over a plane mirror for use as driving mirror.
Date posted: February 7, 2017. Answers (1)
- Explain why the images formed in a pin hole camera gets blurred when the hole is enlarged(Solved)
Explain why the images formed in a pin hole camera gets blurred when the hole is enlarged
Date posted: February 7, 2017. Answers (1)
- State the number of images formed when an object is between two plane mirror placed in parallel(Solved)
State the reason why when a ray of right strikes a mirror at 90o, the reflected ray travels along the a same path as the incident ray
Date posted: February 7, 2017. Answers (1)
- State the number of images formed when an object is between two plane mirror placed in parallel(Solved)
State the number of images formed when an object is between two plane mirror placed in parallel
Date posted: February 7, 2017. Answers (1)
- In certain pinhole camera, the screen is 10cm from the pinhole. When the camera is placed 6 m away from a tree, a sharp image of the tree 16 cm high(Solved)
In certain pinhole camera, the screen is 10cm from the pinhole. When the camera is placed 6 m away from a tree, a sharp image of the tree 16 cm high is formed on the screen. Determine the height of the tree
Date posted: February 7, 2017. Answers (1)
- What is meant by virtual image?(Solved)
What is meant by virtual image?
Date posted: February 7, 2017. Answers (1)
- A vertical object placed on a bench is observed to have three shadows of different sharpness, in different directions(Solved)
A vertical object placed on a bench is observed to have three shadows of different sharpness, in different directions. Explain this observation
Date posted: February 7, 2017. Answers (1)
- What property of light is suggested by the formation of shadows?(Solved)
What property of light is suggested by the formation of shadows?
Date posted: February 7, 2017. Answers (1)
- The melting point of Oxygen is given as -281.3oC. Convert this temperature to Kelvin (K)(Solved)
The melting point of Oxygen is given as -281.3oC. Convert this temperature to Kelvin (K).
Date posted: February 6, 2017. Answers (1)
- In a vacuum flask the walls enclosing the vacuum are silvered on the inside. State the reason for this(Solved)
In a vacuum flask the walls enclosing the vacuum are silvered on the inside. State the reason for this
Date posted: February 6, 2017. Answers (1)
- An electric heater is placed at equal distances from two similar metal cans A and B filled with water at room temperature(Solved)
An electric heater is placed at equal distances from two similar metal cans A and B filled with water at room temperature. The outer surface of can A is shiny while that of can B is dull black. State with reasons which can will be at higher temperature after the heater is switched on for some time.
Date posted: February 6, 2017. Answers (1)
- A wooden bench and a metal bench are both left in the sun for a long time. Explain why the metal bench feels hotter to touch(Solved)
A wooden bench and a metal bench are both left in the sun for a long time. Explain why the metal bench feels hotter to touch.
Date posted: February 6, 2017. Answers (1)
- Give reason why heat transfer by radiation is faster than heat transfer by conduction(Solved)
Give reason why heat transfer by radiation is faster than heat transfer by conduction.
Date posted: February 6, 2017. Answers (1)
- State two variables that must be controlled in an experiment for comparing the thermal conductivities of different metal rods of the same diameter (Solved)
State two variables that must be controlled in an experiment for comparing the thermal conductivities of different metal rods of the same diameter.
Date posted: February 6, 2017. Answers (1)
- When a liquid is heated in a glass flask, its level at first falls then rises. Explain this observation(Solved)
When a liquid is heated in a glass flask, its level at first falls then rises. Explain this observation.
Date posted: February 6, 2017. Answers (1)