Question Discussion & Solution

The correct answer is 37 °C.

Key Points

• The normal temperature of the human body is 37 °C.
• A temperature above 100.4 °F(38°C) most often means you have a fever caused by an infection or illness.
• Normal human body temperature is the prototypical temperature range found in humans.
• The normal human body temperature border is typically stated as 36.5–37 °C (97.7–98.6 °F).
• Human body temperature changes, it depends on gender, age, time of day, exertion level, health status, what part of the body the measurement is taken at, state of consciousness (waking, sleeping, sedated), and emotions.
• Body temperature is kept in the normal range by thermoregulation, in which adaptation of temperature is triggered by the central nervous system.

The correct answer is chemical energy.

Key Points

• The dry cell is a type of electric battery which is used for portable electrical devices.
• Electricity is produced through the dry cells from electrochemical energy. Hence, Option 1 is correct.
• A common dry cell is a zinc-carbon cell.
• The electrolyte is immobilized as a paste by a dry cell, with just enough humidity in it to allow current to flow.
• Like a wet cell, a dry cell can work without spilling in any direction, because there is no free liquid in it.
• The versatility makes it ideal for mobile devices.
• The first wet-cell batteries, in comparison, were usually fragile glass containers featuring lead rods sticking from an open-top.
• Hence, they required careful handling to prevent spillage.
• The dry-cell battery development made a significant advance in battery safety and portability.
• Batteries render electricity from chemical energy.
• Batteries consist of one or more different parts, or cells, which contain an electrolyte called a chemical.
• Every cell has two electrodes that are electrically conductive immersed in its electrolyte.
• The electrodes consist of different materials; one releases electrons into the electrolyte, and the other absorbs them.
• Once an electrical system is attached to the electrodes, an electrical current passes through it and supports its operation with electric power.
• The energy contained in the dry cell is therefore in the form of chemical energy.

Additional Information

• Thermal energy
  • It is also called heat energy 
  • It is produced when a rise in temperature causes atoms and molecules to move faster and collide with each other.
  • The energy that comes from the temperature of the heated substance is called thermal energy.
  • Thermal energy is energy that comes from a substance whose molecules and atoms are vibrating faster due to a temperature rise.
• In physical sciences, mechanical energy
  • It is the sum of potential energy and kinetic energy.
  • It is the macroscopic energy associated with a system.
  • The principle of conservation of mechanical energy states that if an isolated system is subject only to conservative forces, then the mechanical energy is constant.
• Nuclear power
  • It is the use of nuclear reactions to produce electricity.
  • Nuclear power can be obtained from nuclear fission, nuclear decay, and nuclear fusion reactions.
  • Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants.

CONCEPT:

• Plane mirror: This mirror is straight without any inward or outward curve.
  • It forms a virtual image and upright image which is of size as same as the object.
  • The bathroom mirrors are an example.
• Concave mirror: The mirrors curved inside on the reflecting side are called concave mirrors.
  • These mirrors produce a real, inverted, and magnified image of the object.
  • These are used in reflecting telescopes, shaving mirrors, and ophthalmoscope.

• Convex mirror: It is an outward curved mirror that produces a diminished image.
  • Convex mirrors either diverge a parallel beam of light into all directions or gather light from all directions and produce a parallel beam out of it.

EXPLANATION:

• Following are the reasons as to why a convex mirror is used as a rearview mirror in the vehicle

• The image formed by the convex mirror is virtual and erect in contrast to that of the real but inverted image of the concave mirror.
• It gathers light from all directions and aligns it as a parallel beam so that it provides a wider view to the viewer. That's why the convex mirror is used as a rear-view mirror in vehicles. So option 2 is correct.

The correct answer is ​Heat is absorbed.

Key Points

•  When ice is converted into water heat is absorbed by the ice, so the molecules of ice increase their energy and convert into water. Hence option A is correct.
• Additional Information
• The conversion of ice into water is an example of melting. If you took out the ice cubes from the freezer and placed them in a warm room, the ice would absorb energy from the warmer air around them. This absorbed energy would facilitate them to overcome the force of attraction holding them together, enabling them to slip out of the fixed position that they held as ice. The process in which solids change to a liquid is called melting. The melting point is the temperature at which a solid changes to a liquid. 
• The static water is converted to ice It means when the water is converted into ice its potential energy decreases. 
• If we compare the kinetic and potential energy of the water vapor, water and ice then water vapor has the most kinetic as well as potential energy as compared to water and ice.
• This is because the particle of water vapor is free to move and they can move more vigorously. Please note that kinetic energy is associated with moving objects whereas potential energy is associated with a static object. 

The set of given words are Almonds, Cashew, Walnuts all are dry-fruits. 

Apricot is the most similar to that set of word. Remaining Banana, Apple and Watermelon different from Apricot.

Hence, "Apricot" is the correct answer.