2.c
3.b
1.a
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<span>First we can find the circumference of the whole circle with a radius of 5 feet.
circumference = 2 pi radius
circumference = (2 pi) (5 feet)
circumference = (10 pi) feet
From one high point to the other high point, the string moves through an angle of 10 degrees. Since a full circle is 360 degrees, this angle is 1/36 of a full circle.
Therefore, the arc length is 1/36 of the whole circumference.
arc length = (1/36) (circumference)
arc length = (1/36) (10 pi) feet
arc length = 0.873 feet</span>
Answer:
a)Velocity of car =v=16 m/s
b)Force against the track at point B=1.15*
N
Explanation:
Given mass of roller coaster=m=350 kg
Position of A=Ha=25 m
Position of B=Hb=12 m
Net potential energy=mg(ha-hb)
Net potential energy=(350)(9.80)(25-12)
Net potential energy=44590 J
Using energy conservation
net kinetic energy=net potential energy
(1/2)mv^2=mg(ha-hb)
m=350
velocity=v=16 m/s
b)There two force acting,centripetal force upward and gravity downward.
Thus net force acting will be
Net force=(mv^2/r)-mg
Net force=14933.33-3430
Net force=1.15* N
The car at 60 kph has 9 times more kinetic energy than the car traveling at 20 kph. This assumes that both cars have the same mass. Kinetic energy depends on the square of thee speed so if one car is going 3 times faster, its kinetic energy will be 3^2 ( = 9 ) greater. The car going at 60 kph will have 4 times the KE of the car going at 30 kph ( again assuming that the cars have the same mass.)
