Answer:
To decide where the balls land, we need to determine how long the balls are in the air. Both balls will take 2 seconds to hit the ground.
Explanation:
1) Time played forward : gravity & drag forces are in opposite directions so it takes a longer time to reach the ground. 2) Time played backward : gravity & drag forces are in the same direction so it takes a shorter time to reach the ground.
<span>If the Earth rotated more slowly about its axis, your apparent weight would
A) increase.
B) decrease.
C) stay the same.
D) be zero.
</span>A) increase.
Answer:
Explanation:
Charge on uranium ion = charge of a single electron
= 1.6 x 10⁻¹⁹ C
charge on doubly ionised iron atom = charge of 2 electron
= 2 x 1.6 x 10⁻¹⁹ C = 3.2 x 10⁻¹⁹ C
Let the required distance from uranium ion be d .
force on electron at distance d from uranium ion
= 9 x 10⁹ x 1.6 x 10⁻¹⁹ / r²
force on electron at distance 61.10 x 10⁻⁹ - r from iron ion
= 9 x 10⁹ x 3.2 x 10⁻¹⁹ / (61.10 x 10⁻⁹ - r )²
For equilibrium ,
9 x 10⁹ x 1.6 x 10⁻¹⁹ / r² = 9 x 10⁹ x 3.2 x 10⁻¹⁹ / (61.10 x 10⁻⁹ - r )²
2 d² = (61.10 x 10⁻⁹ - r )²
1.414 r = 61.10 x 10⁻⁹ - r
2.414 r = 61.10 x 10⁻⁹
r = 25.31 nm .
Answer:
1 x 10 -10 whisper at 1m distance.
Explanation:
- Properly fitted ear plugs an reduce noise form 15-30db. Although they are better for low frequency