1.
A wedge is a triangular shaped tool that can be used to stop, split, separate or hold an​ object in place. Which of the following things is not a wedge.
Correct Answer
D. Cog
Explanation
A cog is not a wedge because it is a toothed wheel or gear that is used to transmit power or motion between other gears or wheels. It does not have a triangular shape like a wedge and is not used for stopping, splitting, separating, or holding objects in place.
2.
A lever is used to move objects by applying force to them. This force is known as...
Correct Answer
A. Leverage
Explanation
A lever is a simple machine that helps move objects by applying force. The force applied to the lever is known as leverage.
3.
A pulley is used to lift objects. Which of the following things is not part of a pulley?
Correct Answer
D. Mortar
Explanation
A pulley is a simple machine that consists of a wheel and an axle. The wheel is the circular part of the pulley that rotates, while the axle is the rod or spindle around which the wheel rotates. The belt is a flexible loop that wraps around the wheel and transfers motion or force. However, a mortar is not part of a pulley. A mortar is a bowl-shaped container used in grinding or mixing substances, and it is not involved in the operation or function of a pulley.
4.
A wheel and axle move other objects using rotation. Which part of a door is a wheel and axle?
Correct Answer
B. Door Knob
Explanation
A door knob can be considered as a wheel and axle because it allows the door to rotate around its hinges, enabling it to open and close. The knob acts as the wheel, providing a surface for the user to grip and turn, while the axle is the rod that connects the knob to the door, allowing the rotational motion to be transferred.
5.
A screw can tighten, fasten, attach and move another object using force. A screw applies force using the grooves in its body. These grooves are also known as a...
Correct Answer
C. Helix
Explanation
A screw applies force using the grooves in its body, which are known as helix. The helix shape allows the screw to move through another object by rotating it, thus tightening, fastening, attaching, or moving the object.
6.
An inclined plane is a sloping plane used to raise low bodies.
Correct Answer
B. False
Explanation
An inclined plane is not used to raise low bodies, but rather to lower or move them upwards with less effort. It is a simple machine that reduces the force needed to lift an object by increasing the distance over which the force is applied. This allows for easier transportation of heavy objects or for lifting objects to higher levels. Therefore, the correct answer is False.
7.
The wheel and axle increase the friction involved in moving an object.
Correct Answer
B. False
Explanation
The wheel and axle actually reduce the friction involved in moving an object. This is because the wheel and axle system allows for the object to be moved with less effort by distributing the force over a larger distance. The rotation of the wheel and axle also helps to minimize the friction between the object and the surface it is moving on. Therefore, the correct answer is False.
8.
What is the use of screw?
Correct Answer
C. Both A and B
Explanation
The correct answer is "Both A and B." A screw can be used to lift heavy objects by creating a mechanical advantage through its threaded shaft. It can also be used to dig holes by rotating it into the ground. Therefore, both options A and B are valid uses of a screw.
9.
Which type of machine has only one simple machine?
Correct Answer
A. Simple machine
Explanation
A simple machine is a mechanical device that helps in changing the direction or magnitude of a force. It consists of only one simple machine, such as a lever, inclined plane, wheel and axle, pulley, wedge, or screw. Compound machines, on the other hand, are made up of two or more simple machines working together. A fixed pulley is a type of simple machine, but it is not the only type. Therefore, the correct answer is simple machine.
10.
A lightbulb is an example of what simple machine?
Correct Answer
C. Simple machine screw
Explanation
A lightbulb is not an example of an inclined plane, wedge, or pulley. However, it can be considered an example of a simple machine screw. A simple machine screw is a type of inclined plane wrapped around a cylinder, and the threads on the screw allow it to convert rotational motion into linear motion. In the case of a lightbulb, the screw base of the bulb allows it to be easily screwed into a socket, demonstrating the principles of a simple machine screw.