Newtons third law (inertia) is to blame
Set up the problem with the conversion rates as fractions where when you multiply the units cancel out leaving the desired units behind.
<u>We are given:</u>
Mass of the rocket = 10 kg
Weight of the Rocket = 100 N
Upward thrust applied by the rocket = 400 N
<u>Net upward force on the rocket:</u>
We are given that gravity pulls the rocket with a force of 100 N
Also, the rocket applied a force of 400N against gravity
Net upward force = Upward thrust - Force applied by gravity
Net upward force = 400 - 100
Net upward force = 300 N
<u>Upward Acceleration of the Rocket:</u>
From newton's second law:
F = ma
<em>replacing the variables</em>
300 = 10 * a
a = 30 m/s²
Answer:
1. -8.20 m/s²
2. 73.4 m
3. 19.4 m
Explanation:
1. Apply Newton's second law to the car in the y direction.
∑F = ma
N − mg = 0
N = mg
Apply Newton's second law to the car in the x direction.
∑F = ma
-F = ma
-Nμ = ma
-mgμ = ma
a = -gμ
Given μ = 0.837:
a = -(9.8 m/s²) (0.837)
a = -8.20 m/s²
2. Given:
v₀ = 34.7 m/s
v = 0 m/s
a = -8.20 m/s²
Find: Δx
v² = v₀² + 2aΔx
(0 m/s)² = (34.7 m/s)² + 2 (-8.20 m/s²) Δx
Δx = 73.4 m
3. Since your braking distance is the same as the car in front of you, the minimum safe following distance is the distance you travel during your reaction time.
d = v₀t
d = (34.7 m/s) (0.56 s)
d = 19.4 m