Answer:
a) 20 m/s
b) 37.5 m)s
Explanation:
Average speed = total distance ÷ total time
=> (a) average speed of a car that travels 400m in 20s
= 400/20 = 20 m/s
& (b) average speed of an athlete who runs 1500m in 4 minutes (or 4×60=240 seconds)
= 1500/240 = 37.5 m/s
Answer:
I think B but im not sure
Explanation:
(0.5)×(0squared)×(3)=(1.5j)
Answer:

Given:
Initial velocity (u) = 30 m/s
Final speed (v) = 0 m/s
Acceleration (a) = - 1.5 m/,s²
To Find:
Time in which train will come to rest (t).
Explanation:

So,
Time in which train will come to rest = 20 seconds
Answer:
4960 N
Explanation:
First, find the acceleration.
Given:
v₀ = 6.33 m/s
v = 2.38 m/s
Δx = 4.20 m
Find: a
v² = v₀² + 2aΔx
(2.38 m/s)² = (6.33 m/s)² + 2a (4.20 m)
a = -4.10 m/s²
Next, find the force.
F = ma
F = (1210 kg) (-4.10 m/s²)
F = -4960 N
The magnitude of the force is 4960 N.