Question Discussion & Solution

The correct answer is Ammeter. 

Key Points

• An ammeter is the instrument used to measures the electric current in a circuit.
• Electricity is the flow of free electrons.
• Unit of Current - Ampere.
• Father of  Electricity - Michael Faraday. 

Additional Information

Ohmmeter

• The instrument used to measure the electrical resistance.
• Electrical resistance opposes the flow of electric current in a circuit.
• Unit of Resistance - Ohm
• Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points.
• V=IR, where (R) Resistance is the proportionality constant.

Thermometer

• An instrument used to measure the temperature.
• The first Mercury Thermometer was invented by Gabriel Fahrenheit.

​Gyroscope

• The instrument used to measure or maintaining the orientation of angular velocity.
• Gyroscope was invented by Leon Foucault.

Let the three consecutive numbers be x, x + 1, x + 2

⇒ x + (x + 1) + (x + 2) = 345

⇒ 3x + 3 = 345

⇒ 3x = 345 – 3 = 342

\(\Rightarrow x = \frac{{342}}{3} = 114\)

So the three consecutive numbers are 114, 115 and 116. And the middle number is 115.

CONCEPT:

Nuclear reactor:

• In a nuclear reactor, the energy is generated by a nuclear fission reaction.
• In a nuclear reactor, there is a concrete chamber and in this concrete chamber, there is a steel vessel. In this steel vessel, the nuclear fission reaction takes place.
• Fuel rods: Fuel rods are placed inside the steel chamber.
  • These rods are made of fissionable material. Generally, fuel rods are made of uranium-235, thorium, etc.
• Moderator: It is used to decrease the speed of fast-moving neutrons.
• Control rods: These rods are placed between the fuel rods. It is used to control the chain reaction. Control rods are generally made of cadmium.
  • The nuclear reactors are controlled by means of control rods which are made of a strongly neutron-absorbent material such as boron or cadmium (Cd).
• Coolant: It is used to absorb heat produced during the reaction.

EXPLANATION:

• Moderators are used to slow down the neutrons in order to carry out effective nuclear fission and also absorb neutrons. 
• The main reason why heavy water is used as the moderator is that it captures less number of neutrons compared to normal water Hence, option 2 is the answer. 

In this question we shows that Pen is used for Writing.

Similarly, Spoon is used for Eating.

But Gun comes under Weapon, Teacher teach in School and Eraser and Pencil is different things.

Option 1, 3 and 4 is not correct.

Hence, "Spoon : Eating" is the correct answer. 

The correct answer is A Central processing unit.

Key Points

• Central Processing Unit(CPU)
  • A CPU is also called a central processor, main processor, or just processor, is the electronic circuitry that executing instructions comprising a computer program.
  • The CPU performs basic arithmetic, logic, controlling, and input/output operations specified by the instructions in the program.
  • The fundamental operation of most CPU's regardless of the physical form they take is to execute a sequence of stored instructions called a program. 
• Instructions cycle in CPU
  • All CPU's follows the following steps in order to complete their operations:
    1. Fetch: The first step, involves retrieving instructions from the program memory.
    2. Decode: The instruction that the CPU fetches from the memory determines what the CPU will do, which is decoded by the instructor decoder.
    3. Execute: In this step, all the desired functions are performed as per the instructions decoded.
• Intel Core
  • ​Intel core are streamlined computers CPU marketed by Intel Corporation.
  • Brand Names: Core, Core 2, Core i3, Core i5, Core i7, Core i9
  • Launched: January 2006
  • Founders: Gordon Moore Robert Noyce
  • Headquarters: Santa Clara, California, USA

Additional Information