A pendulum oscillates 30 times in 3 seconds. Choose the correct statement from among the following:
(A) It's time period is 10 s and frequency 3 Hz.
(B) It's time period is 0.1 s and frequency is 10 Hz.
(C) It's time period is 10 s and frequency is 03 Hz.
(D) It's time period is 0.3 s and frequency is 0.3 Hz
We can do this by dividing the number of oscillations (30) by the total time taken (3 seconds): Frequency = 30 oscillations / 3 seconds = 10 Hz Therefore, the correct statement is B. Its time period is 0.1 s and frequency is 10 Hz
A light bulb working on an 18 V battery draws a current of 3 A. What will be the resistance of the bulb?
(A) 6 Ω
(B) 2 Ω
(C) 4 Ω
(D) 3 Ω
An electric bulb running on 18 V battery draws 3A of electric current. The resistance of the bulb will be 6 Ω.
In which year did Albert Einstein predict a new state of matter, the Bose-Einstein condensate (BEC), based on a quantum formulation by the Indian physicist Satyendra Nath Bose?
(A) 1935
(B) 1924
(C) 1930
(D) 1919
1. In which year did Albert Einstein predict a new state of matter, Bose-Einstein condensate (BEC) in 1924, based on the quantum formulation given by Indian physicist Satyendra Nath Bose?
2. Bose–Einstein condensate (BEC) is a state of matter in which a group of boson particles are in the same quantum state.
Which scientist suggested that the magnet must exert an equal and opposite force on the current-carrying conductor?
(A) Michael Faraday
(B) Andre Marie Ampere
(C) Joseph Henry
(D) William Gilbert
1. French scientist Andre-Marie Ampère suggested that a magnet should also exert an equal and opposite force on a current-carrying conductor.
2. A current-carrying wire has its own magnetic field.
3. A current-carrying wire attracts a magnetic material like a normal bar magnet.
4. When the current is withdrawn or the switch is closed, there is no magnetic effect in that case.
5. This phenomenon was called the magnetic effect of current.
Identify the correct statement.
(A) The resistance of a wire depends on the length and density of the wire.
(B) Specific resistance is the same for all conductors.
(C) Resistance of a wire depends on the length and cross-section of the wire.
(D) Specific resistance is dependent on the cross-sectional area of the wire.
1. Resistance of a wire depends on the length and cross-section of the wire.
Mechanical energy is the sum of potential energy and ______ energy.
(A) kinetic
(B) heat
(C) electrical
(D) chemical
1. Mechanical energy is a combination of kinetic energy and potential energy.
2. Mechanical energy is defined as the sum of kinetic energy and potential energy used to do work on an object.
3. Mechanical energy is the form of energy that is related to the position and motion of an object.
What are modern powerful magnets made of?
(A) Iron compounds
(B) Ferromagnetic materials
(C) Alloys of aluminium, cobalt and nickel
(D) Alloys of iron, cobalt and nickel
The strongest permanent magnets in the world are neodymium (Nd) magnets, they are made from magnetic material made from an alloy of neodymium, iron and boron to form the Nd2Fe14B structure.
When is the maximum fuel consumption during the round trip to the Moon?
(A) To overcome the gravity of the earth while flying
(B) To overcome the gravity of the moon on landing on the moon
(C) To overcome the gravity of the moon while flying from the moon
(D) In re-entering the earth and overcoming the gravity of the earth in a soft landing
Maximum fuel is consumed when the spaceship has to reach the greatest velocity. We know that the velocity required to escape the gravitational pull of Earth is more than the velocity required to escape the gravitational pull of the Moon.
What does the letter 'G' stand for in '2G Spectrum'?
(A) Gerwens
(B) Global
(C) Generation
(D) Google
The G in 2G, 3G and 4G stands for Generation, and they refer to the 2nd, 3rd and 4th generation of wireless technology. The higher the generation the better, fast, and powerful will be the network.
Why don't birds feel shortness of breath while flying at high altitudes?
(A) Their lungs are very large
(B) They fly passively
(C) They have additional air sacs
(D) They use less oxygen
Because flying takes a tremendous amount of energy, birds need to get lots of oxygen. The air sacs in their lungs help them to keep fresh air flowing in, unlike mammals, where the “old” air within the trachea and mouth (which has low oxygen content and high CO2 levels) in inhaled each time.
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