The apparent weight of a person in an elevator moving downwards with an acceleration 'a' (where a < g) is:
A. Greater than true weight
B. Less than true weight
C. Zero
D. Equal to true weight
Answer: Option B
Solution (By JKSSB Mock Tests)
When an elevator moves downwards with acceleration 'a', the net downward force on the person is mg - R = ma, where R is the normal reaction (apparent weight). Solving for R gives R = m(g - a). Since g - a is less than g, the apparent weight (R) is less than the true weight (mg).
Explanation:
Seconds pendulum has time period of 2 seconds (1 s for half swing). Frequency f = 1/T = 1/2 = 0.5 Hz. Length about 99.4 cm on Earth. Not exactly 1 m.
No comments yet. Be the first to start the discussion!