Answer:
v = 8.45 m/s
Explanation:
given,
mass = 3 kg
angle = 30.0°
vertical distance = 3.3 m
μ = 0.06
according to conservation of energy
KE(loss) = PE(gain) + Work done (against\ friction)..............(1)
frictional Force
work against friction
W = F d
Potential energy
PE = mgh
v = 8.45 m/s
the minimum speed is equal to 8.45 m/s
It can’t be b because that will increase the dissolving rate
Average speed of the car is defined as the ratio of total distance and total time
So here we will have
now we know that
time = 5 h
now from above equation we will have
so the average speed will be 90 km/h
Well, Break the problem up into parts.
For speeding up:
The car accelerates at 4 m/s^2 for 3 seconds. Multiplying these values tells you the car reaches a speed of 12 m/s.
Vf^2 = Vi^2 + 2a(Xf - Xi)
12^2 = 0 + 2(4)(Xf - 0)
144 = 8 Xf
Xf = 18 m
For coasting:
The car is at the 12 m/s and does this for 2 seconds.
x = vt = (12)(2) = 24 m
For slowing down:
The car decelerates at 3 m/s^2 to come to a stop at the next sign. From 12 m/s, this would take 12/3 seconds or 4 s.
Vf^2 = Vi^2 + 2a(Xf - Xi)
0 = 12^2 + (2)(-3)(Xf - 0)
-144 = -6 Xf
Xf = 24 m
Summing the distances: Xtotal = 18 + 24 + 24 = 66 m
Continental drift was a theory that explained how continents shift position on Earth's surface. Set forth in 1912 by Alfred Wegener, a geophysicist and meteorologist, continental drift also explained why look alike animal and plant fossils, and similar rock formations, are found on different continents
