Answer:
Zero (0)
Explanation:
A horizontal line will be no movement of negative of positive acceleration
1. a=Δv/Δt=(v-vo)/t=(0-25)/5=-25/5=-5 m/s²
The "-" sign shows us that the car has a slow motion
2.a=Δv/Δt=(v-vo)/t=(10-0)/4=10/4=2,5 m/s²
3.they do not have acceleration because they go at constant speed
Answer:
The speed is 3.87 m/s
Explanation:
The total work is equal to the change to kinetic energy:
Wtotal = ΔEk
Wspring + Wfriction = Ekf - Eki
Eki = 0

Where
k = 200 N/m
d = 10 cm = 0.1 m
fk = 0.15
m = 2 kg
g = 9.8 m/s²
vi = 4 m/s
Replacing and clearing v:

Because weight W = M g, the ratio of weights equals the ratio of masses.
(M_m g)/ (M_w g) = [ (p^2 Man )/ (2 K_man)] / [ (p^2 Woman )/ (2 K_woman)
but p's are equal, so
K_m/K_m = (M_w g)/(M_m g) = W_woman / W_man = 450/680 = 0.662