Answer:
a) -1.25 m/s²
b) 62.5 m
Explanation:
Convert km/h to m/s:
45 km/h × (1000 m/km) × (1 h / 3600 s) = 12.5 m/s
a = Δv / Δt
a = (0 m/s − 12.5 m/s) / 10 s
a = -1.25 m/s²
Δx = ½ (v + v₀) t
Δx = ½ (0 m/s + 12.5 m/s) (10 s)
Δx = 62.5 m
I think it’s C. Marshmallow and toothpicks are used to show the composition of a water molecule
There’s many terms to it
1 : to keep in a safe or sound state He conserved his inheritance. especially : to avoid wasteful or destructive use of conserve natural resources conserve our wildlife. 2 : to preserve with sugar. 3 : to maintain (a quantity) constant during a process of chemical, physical, or evolutionary change conserved DNA ...
Answer:
(a) the high of a hill that car can coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h is 47.6 m
(b) thermal energy was generated by friction is 1.88 x
J
(C) the average force of friction if the hill has a slope 2.5º above the horizontal is 373 N
Explanation:
given information:
m = 750 kg
initial velocity,
= 110 km/h = 110 x 1000/3600 = 30.6 m/s
initial height,
= 22 m
slope, θ = 2.5°
(a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h?
according to conservation-energy
EP = EK
mgh = 
gh = 
h = 
= 47.6 m
(b) If, in actuality, a 750-kg car with an initial speed of 110 km/h is observed to coast up a hill to a height 22.0 m above its starting point, how much thermal energy was generated by friction?
thermal energy = mgΔh
= mg (h -
)
= 750 x 9.8 x (47.6 - 22)
= 188160 Joule
= 1.88 x
J
(c) What is the average force of friction if the hill has a slope 2.5º above the horizontal?
f d = mgΔh
f = mgΔh / d,
where h = d sin θ, d = h/sinθ
therefore
f = (mgΔh) / (h/sinθ)
= 1.88 x
/(22/sin 2.5°)
= 373 N
Answer:
D
Explanation:
If it is of very high intensity it will be 85-100%