A roller coaster is stopped on a track. When the engineer presses a launch button on the coaster, the coaster moves forward. Explain this change in terms of balanced and unbalanced forces.
Answer:
D
Explanation:
First we define our variables
V0=29.4
a=-9.8
V=0
We have to find the maximum displacement , which I will define as X
We use formula v^2=v0^2+2aX
All we do is substitute our values
0=29.4^2-19.6X
29.4^2=19.6X
X=29.4^2/19.6=44.1
Answer:
Explanation:
given,
length of the ship = 120 m
length of model of the ship = 4 m
Speed at which the ship travels = 70 km/h
speed of model = ?
by using froude's law
for dynamic similarities
hence, the velocity of model will be 12.78 km/h
Answer:
C. 85%
Explanation:
A cylinder fitted with a piston exists in a high-pressure chamber (3 atm) with an initial volume of 1 L. If a sufficient quantity of a hydrocarbon material is combusted inside the cylinder to produce 1 kJ of energy, and if the volume of the chamber then increases to 1.5 L, what percent of the fuel's energy was lost to friction and heat?
A. 15%
B. 30%
C. 85%
D. 100%
work done by the system will be
W=PdV
p=pressure
dV=change in volume
3tam will be changed to N/m^2
3*1.01*10^5
W=3.03*10^5*(1.5-1)
convert 0.5L to m^3
5*10^-4
W=3.03*10^5*5*10^-4
W=152J
therefore
to find the percentage used
152/1000*100
15%
100%-15%
85% uf the fuel's energy was lost to friction and heat
