1.
The transfer of energy that occurs when a force makes an object move a distance.
Correct Answer
B. Work
Explanation
Work is defined as the transfer of energy that occurs when a force is applied to an object and it moves a certain distance. In other words, work is done when force is exerted on an object to move it. The unit of work is joule, which is equal to the amount of work done when a force of one newton is applied to move an object one meter. Power, on the other hand, is the rate at which work is done, while force is the push or pull applied to an object.
2.
A golf club is an example of this class of lever:
Correct Answer
B. Third class
Explanation
A golf club is an example of a third-class lever because the effort (force applied by the golfer) is placed between the fulcrum (the golfer's hands on the grip) and the load (the clubhead striking the ball). In a third-class lever, the effort arm is shorter than the load arm, resulting in a mechanical disadvantage. This means that the effort applied by the golfer needs to be greater than the load (the weight of the clubhead and the force needed to strike the ball) in order to achieve the desired result.
3.
SI unit for power.
Correct Answer
B. Watt
Explanation
The SI unit for power is the Watt. Power is defined as the rate at which work is done or energy is transferred. The Watt is a derived unit of power in the International System of Units (SI), named after the Scottish engineer James Watt. It is equivalent to one joule per second, representing the amount of energy transferred or work done per unit time. The unit is commonly used to measure the power output of electrical devices, such as light bulbs, motors, and appliances.
4.
All of these are examples of inclined plane except:
Correct Answer
A. Wheel
Explanation
An inclined plane is a flat surface that is tilted at an angle, which allows objects to be moved up or down with less force. A wheel, on the other hand, is not an inclined plane. It is a circular object that rotates around an axis. While a wheel can be used in conjunction with an inclined plane, it is not an example of an inclined plane itself.
5.
The amount of work down per unit of time
Correct Answer
D. Power
Explanation
Power is the correct answer because it is defined as the amount of work done per unit of time. In other words, power measures how quickly work is being done. It takes into account both the amount of work being done and the time it takes to do that work. Power is often measured in watts and is a key concept in physics and engineering.
6.
What word means “the ability to do work?”
Correct Answer
B. Energy
Explanation
Energy is the correct answer because it refers to the ability to do work. It is a fundamental concept in physics and is defined as the capacity to cause change or perform tasks. Energy exists in various forms such as kinetic, potential, thermal, and electrical. It is a scalar quantity and is measured in joules. Force, acceleration, and joule are all related concepts but do not directly represent the ability to do work.
7.
What are two types of energy?
Correct Answer
C. Kinetic energy and potential energy
Explanation
The correct answer is kinetic energy and potential energy. Kinetic energy is the energy possessed by an object due to its motion, while potential energy is the energy possessed by an object due to its position or condition. Both types of energy are fundamental concepts in physics and are used to describe and analyze various phenomena and systems.
8.
Gravitational potential energy is energy due to
Correct Answer
D. Height
Explanation
Gravitational potential energy is the energy possessed by an object due to its position in a gravitational field. The higher an object is from the ground, the greater its gravitational potential energy. Therefore, the correct answer is "height" because the energy is directly related to the vertical distance or height of the object from a reference point, such as the ground.
9.
Which type of pulley system as the highest mechanical advantage?
Correct Answer
C. Pulley system
Explanation
A pulley system has the highest mechanical advantage compared to a fixed or moveable pulley system because it utilizes multiple pulleys working together. This allows for a greater reduction in the amount of force needed to lift an object. In a pulley system, the load is distributed among multiple strands of rope, which decreases the force required to lift the load. This makes the pulley system more efficient and provides a higher mechanical advantage compared to a single fixed or moveable pulley.
10.
A simple machine that is a rigid bar that has to move around a fixed point called a fulcrum.
Correct Answer
A. Lever
Explanation
A lever is a simple machine that consists of a rigid bar that pivots around a fixed point called a fulcrum. This allows the lever to exert a mechanical advantage, making it easier to lift or move heavy objects. The other options, inclined plane, wedge, and screw, do not involve a fulcrum or a pivoting motion, making them incorrect answers.
11.
What is the SI unit for work or energy?
Correct Answer
A. Joule
Explanation
The SI unit for work or energy is the joule. This unit is used to measure the amount of energy transferred when a force of one newton is applied over a distance of one meter. The joule is a derived unit, combining the fundamental units of mass, length, and time. It is widely used in physics and engineering to quantify various forms of energy, such as mechanical, electrical, and thermal energy.
12.
A wheel barrow is which class of lever?
Correct Answer
B. Second class
Explanation
A wheelbarrow is classified as a second-class lever because the load is located between the fulcrum (the wheel) and the effort (the person pushing or pulling the handles). In a second-class lever, the load is closer to the fulcrum than the effort, which allows for a mechanical advantage, making it easier to lift heavy loads.
13.
What is the net force on a 1,000 kg object accelerating at 3 m/s2?
Correct Answer
B. 3000 N
Explanation
The net force on an object can be calculated using the equation F = m*a, where F is the force, m is the mass, and a is the acceleration. In this case, the mass of the object is given as 1,000 kg and the acceleration is given as 3 m/s^2. Plugging these values into the equation, we get F = 1,000 kg * 3 m/s^2 = 3,000 N. Therefore, the net force on the object is 3,000 N.
14.
The force exerted on an object by a machine may be called any of the following except.
Correct Answer
B. Input force
Explanation
The force exerted on an object by a machine is commonly referred to as the input force. This force is typically applied to the machine in order to produce a desired output force or to overcome a resistance. The terms "output force," "load," and "resistance" all refer to different aspects of the force exerted on the object, but they do not describe the force applied to the machine itself. Therefore, the correct answer is input force.
15.
. In which of the following is no work done?
Correct Answer
C. Pushing on a wall
Explanation
Pushing on a wall does not involve any displacement of the object being pushed. In order for work to be done, there must be a force applied and a displacement in the direction of the force. Since the wall does not move, there is no displacement and therefore no work is done.
16.
A knife is an example of which kind of simple machine?
Correct Answer
C. Wedge
Explanation
A knife is an example of a wedge because it has a sharp, pointed edge that is used to separate or cut through objects. The shape of a wedge allows for increased force to be applied over a smaller area, making it easier to perform tasks such as slicing or splitting. The inclined plane of a wedge allows it to penetrate materials with less effort, making it a useful tool for various applications.
17.
A flag pole is an example of this type of pulley:
Correct Answer
B. Fixed
Explanation
A flag pole is an example of a fixed pulley because it is attached to a stationary object, such as a building or a pole, and does not move. In a fixed pulley, the load is lifted or lowered by pulling the rope or cable, while the pulley remains in a fixed position. In the case of a flag pole, the rope is pulled to raise or lower the flag, but the pulley itself does not move.
18.
Kinetic Energy is energy of motion.
Correct Answer
A. True
Explanation
Kinetic energy is the energy possessed by an object due to its motion. It is directly proportional to the mass of the object and the square of its velocity. When an object is in motion, it has the ability to do work or transfer energy to another object upon collision. Therefore, it can be concluded that kinetic energy is indeed the energy of motion.
19.
The closer the threads are together on a screw the greater the mechanical advantage.
Correct Answer
A. True
Explanation
The statement is true because when the threads of a screw are closer together, it means that there are more threads per unit length. This results in a greater mechanical advantage because it requires less force to turn the screw. The force applied to the screw is spread out over a shorter distance, making it easier to rotate and providing a greater mechanical advantage.
20.
Potential Energy is stored energy.
Correct Answer
A. True
Explanation
Potential energy is a type of energy that an object possesses due to its position or condition. It is stored energy because it is not currently being used or converted into another form of energy. When an object is at a height or stretched or compressed, it has potential energy. Therefore, the statement that potential energy is stored energy is true.