Question Discussion & Solution

Option 1 is the correct answer: Local Area Network (LAN) has the highest transmission speed.

The correct answer is Its momentum is doubled.

Key Points

• Momentum is a vector quantity; it has both magnitude and direction.
• Isaac Newton’s second law of motion states that the time rate of change of momentum is equal to the force acting on the particle.
• Momentum can be calculated by multiplying the mass of an object by its forward velocity. (mv = kg*m/s).
• Mass and velocity are both directly proportional to the Momentum.
  • If you increase either mass or velocity, the Momentum of the object increases proportionally.
  • If you double the mass or velocity, you double the Momentum.
  • If you halve the mass or velocity, you half the Momentum.
• Newton's laws of motion-
  • ​Newton’s first law states that if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by force. This postulate is known as the law of inertia.
  • Newton’s second law is a quantitative description of the changes that a force can produce in a body's motion. It states that the time rate of change of a body's momentum is equal in both magnitude and direction to the force imposed on it. The momentum of a body is equal to the product of its mass and its velocity.
  • Newton’s third law states that when two bodies interact, they apply forces to one another equal in magnitude and opposite in direction. The third law is also known as the law of action and reaction. This law is important in analyzing static equilibrium problems, where all forces are balanced, but it also applies to bodies in uniform or accelerated motion.

Important Points

• Acceleration, the rate at which velocity changes with time in terms of both speed and direction. A point or an object moving in a straight line is accelerated if it speeds up or slows down. Motion on a circle is accelerated even if the speed is constant because the direction is continually changing.
• Kinetic energy, a form of energy that an object or a particle has because of its motion. If work, which transfers energy, is done on an object by applying a net force, the object speeds up and gains kinetic energy. Kinetic energy is a property of a moving object or particle and depends not only on its motion but also on its mass.
• Potential energy, stored energy that depends upon the relative position of various parts of a system. Spring has more potential energy when it is compressed than stretched. A steel ball has more potential energy raised above the ground than it has after falling to Earth.

The variable is the basic unit of storage in a Java program. A variable is defined by the combination of an identifier, a type, and an optional initializer.

Variable names cannot be keyword, it is case- sensitive and the first character must be a letter.

In Java, all variables must be declared before they can be used. The basic form of a variable declaration is:

type identifier [ = value ][, identifier [= value ] …];

Examples:

int a, b;

int a = 10, b = 20, c = 30;

int a, b = 20, c;

Confusion point

In Java, variable name can also start with underscore character “_”, or a dollar sign “$”.

Best Possible answer is chosen.

The correct answer is Daya Bai.

Key Points 

• Daya Bai-
  • She was born in Dehra village, Alwar.
  • She was the disciple of Charandas ji.
  • The Daya Bodh and Vinaya Malika texts were written by her.

Additional Information 

• Meera Bai was a disciple of Sant Raidas Ji, Tika Ra Govinda, Narsi Mehta Ri Hundi, Rukmani Mangal, and Meera Padvaliya were written by her.
• Ratan Kumari Jhali was the disciple of Raidas Ji and was Mirabai's mother-in-law.
• Sahajo Bai was the disciple of Charandas Ji.
  • Sahaj Prakash Granth was written by her.

The correct answer is Open Cast Mining.

• Open Cast Mining is the process under which minerals are mined near the earth's surface.

Key Points

• Opencast mining is the process that involves the removal of ore from seams relatively near the surface by means of an open-pit.
• These mines occupy a large area of land for excavation of the ore and disposal of the overburden.

Additional Information

• Drilling is a cutting process which uses a drill bit to cut a hole of circular cross-section in solid materials or ground.
• Quarrying is the process of removing rock, sand, gravel or minerals from the ground in order to use them to produce materials for construction or other uses.
• Shaft mining is the process where miners dig straight down until they reach their desired depth.