1.
The diagram shows a simple cathode-ray tube.Which part emits the electrons?
Correct Answer
B. B
Explanation
In a cathode-ray tube, the part that emits the electrons is the cathode. The cathode is negatively charged and when a voltage is applied, it releases a stream of electrons. These electrons are then accelerated towards the anode, creating a beam of electrons that can be manipulated to create images on the screen. Therefore, option B is the correct answer as it represents the cathode in the diagram.
2.
Charged particles are emitted from the cathode of an oscilloscope.What is the name and the charge of these particles?
Correct Answer
A. A
Explanation
Charged particles emitted from the cathode of an oscilloscope are called electrons. Electrons have a negative charge.
3.
In order to produce a beam of cathode rays, a heated filament is placed near to anWhat is the type of charge on the anode and why is this charge chosen?
Correct Answer
C. C
Explanation
The type of charge on the anode is positive. This charge is chosen because cathode rays are negatively charged particles, so they are attracted to the positively charged anode.
4.
The diagram shows a cathode-ray tube.A student wants the cathode rays to make a spot at P on the screen.Which parts of the cathode-ray tube should be positive?
Correct Answer
A. Anode and top Y plate
Explanation
In a cathode-ray tube, the cathode emits electrons which are accelerated towards the anode due to the potential difference between them. The anode is positively charged, attracting the negatively charged electrons. The electrons then pass through the deflection plates, which are perpendicular to each other. The purpose of the deflection plates is to control the path of the electrons and make them hit a specific spot on the screen. In this case, the student wants the spot at point P on the screen. To achieve this, the top Y plate should be positive, as it will repel the electrons upwards, and the anode should also be positive, as it will attract the electrons towards it.
5.
A cathode-ray tube has an anode and an earthed cathode.Which line in the table shows the charge and the temperature of the anode?A
Correct Answer
C. C
Explanation
The line in the table that shows the charge and the temperature of the anode is C.
6.
A cathode-ray beam passes through an electric field between charged parallelplates.In which direction is the beam deflected?
Correct Answer
B. Towards the positive plate
Explanation
The cathode-ray beam is deflected towards the positive plate because the beam consists of negatively charged particles (electrons). When the beam passes through the electric field between the charged parallel plates, the positive plate attracts the negatively charged electrons, causing them to move towards it. Therefore, the beam is deflected towards the positive plate.
7.
The diagram below shows the screen of a cathode-ray oscilloscope tube.The tube is placed between a pair of charged plates.Which diagram shows the new position of the spot?
Correct Answer
B. B
Explanation
In a cathode-ray oscilloscope tube, the spot on the screen is created by a beam of electrons emitted from the cathode and deflected by the charged plates. When the charged plates are rearranged, the electric field between them changes, causing the beam of electrons to be deflected in a different direction. Therefore, the new position of the spot on the screen will be shown in diagram B.
8.
A beam of cathode rays is entering the space between two charged metal plates.What sort of particles make up cathode rays?
Correct Answer
B. Electrons
Explanation
Cathode rays are composed of electrons. This is because cathode rays are produced when a high voltage is applied across a cathode and an anode in a vacuum tube, causing electrons to be emitted from the cathode. These electrons then travel in a straight line towards the anode, forming the cathode rays. Therefore, the correct answer is electrons.
9.
The figure shows a type of tube in which cathode rays can be produced.A potential difference (p.d.) is connected between two terminal in order to cause thermionic emission. Between which two of the four labelled terminals is the p.d. connected?
Correct Answer
D. Between C and D
Explanation
The correct answer is between C and D. This is because in a cathode ray tube, the cathode (negative electrode) is connected to terminal D, and the anode (positive electrode) is connected to terminal C. The potential difference (p.d.) is applied between the cathode and the anode to create an electric field that accelerates the cathode rays towards the anode. Therefore, the p.d. is connected between terminals C and D.
10.
The figure shows a type of tube in which cathode rays can be produced.What occupies the remaining space in the tube?
Correct Answer
D. Vacuum
Explanation
The figure shows a type of tube in which cathode rays can be produced. In order for cathode rays to be produced, the tube must be evacuated of all air particles. This creates a vacuum inside the tube, meaning that there is no air or any other particles occupying the remaining space. Therefore, the correct answer is Vacuum.