Question

Which of the options is / are CORRECT?
A. The cap of a water bottle is tightened by rotating it in the clockwise direction (as seen from the top).
B. To turn on a tap, the tap head is rotated clockwise; to turn it off it is rotated counter-clockwise (as seen from the top).
C. To loosen a nut of a car wheel, a spanner is turned counter-clockwise (from the point of view of the person using the spanner).
D. The earth as seen from the North Pole rotates clockwise about its axis.

• A. A
• B. B
• C. C
• D. D

Hint:

Remember the simple mnemonic "Righty-Tighty, Lefty-Loosey" for almost all threaded items. For planetary rotation, remember that from the North Pole, Earth rotates counter-clockwise.

Answer 1

The Correct Option is A, C

Step 1: Understanding the Question:
This question tests our knowledge of standard conventions for rotational direction (clockwise and counter-clockwise) in everyday mechanical and physical systems.
Step 2: Key Formula or Approach:
The "right-hand grip rule" is a common principle for threaded objects like screws, nuts, and bottle caps. If you curl the fingers of your right hand in the direction of rotation, your thumb points in the direction of linear motion.
Clockwise ("righty-tighty"): Rotation to the right tightens or moves the object away from the viewer.
Counter-clockwise ("lefty-loosey"): Rotation to the left loosens or moves the object towards the viewer. Step 3: Detailed Explanation (Evaluating the Options):

A. The cap of a water bottle is tightened by rotating it in the clockwise direction (as seen from the top). This follows the "righty-tighty" rule. This statement is CORRECT.
B. To turn on a tap, the tap head is rotated clockwise; to turn it off it is rotated counter-clockwise (as seen from the top). This is the opposite of the standard convention for most taps. Typically, taps are turned on (opened) by rotating counter-clockwise and turned off (closed) by rotating clockwise. This statement is INCORRECT.
C. To loosen a nut of a car wheel, a spanner is turned counter-clockwise (from the point of view of the person using the spanner). This follows the "lefty-loosey" rule. This statement is CORRECT.
D. The earth as seen from the North Pole rotates clockwise about its axis. The Earth, when viewed from above the North Pole, rotates in a counter-clockwise direction. This is why the sun appears to rise in the east and set in the west. This statement is INCORRECT. Step 4: Final Answer:
The correct statements are A and C.