Answer:
3.2 seconds
Explanation:
When the cars collide, they have the same position.
x₁ = x₂
-4 + 1.1t = 8.8 − 2.9t
4t = 12.8
t = 3.2
Answer:
its due to less surface area of action
pressure is high
Answer:
Explanation:
Total heat = Work done = Force × distance
distance = 0.075 × 12 = 0.9 m
W = 45 × 0.9 = 40.5 joules
Specific heat of the human hand = 3.5 kj/kg = 3.5 j/g
Q = MCΔT
ΔT = (Q) ÷ (MC)
ΔT = 40.5 ÷ (3.5 × 1) = 11.57°C
We know that the Delta E + W(Work done by non-conservative
forces) = 0 (change of energy)
In here, the non-conservative force is the friction force
where f = uN (u =kinetic friction coefficient)
W= f x d = uNd ; N=mg
Delta E = 1/2 mV^2 -1/2mVi^2
umgd + 1/2mV^2 - 1/2mVi^2 = 0 (cancel out the m term)
This will then give us:
1/2Vi^2-ugd = 1/2V^2
V^2 = Vi^2 - 2ugd
So plugging in our values, will give us:
V= Sqrt (5.6^2 -2.3^2)
=sqrt (26.07)
= 5.11 m/s