'A' is correct. B, C, and D are false statements.
Answer:
180 m
Explanation:
Case 1.
U = 40 km/h = 11.1 m/s, V = 0, s = 20 m
Let a be the acceleration.
Use third equation of motion
V^2 = u^2 + 2 as
0 = 11.1 × 11.1 - 2 × a × 20
a = 3.08 m/s^2
Case 2.
U = 220 km/h = 33.3 m/s, V = 0
a = 3.08 m/s^2
Let the stopping distance be x.
Again use third equation of motion
0 = 33.3 × 33.3 - 2 × 3.08 × x
X = 180 m
Answer:
Sorry @Josh2013, the answer is B. heart beating.
Explanation:
The reason for this answer is heart beating is an involuntary action, it happens on it's own. Eating, sleeping, and crying are all voluntary actions. And a behavior is an action you do voluntarily.
You could attach both springs to the ceiling and hang the same mass from both. The one that stretches less has the larger spring constant value.
