Acceleration = (change in speed) / (time for the change)
change in speed = (ending speed) - (starting speed)
change in speed = (10 m/s) - (2 m/s) = 8 m/s
Acceleration = (8 m/s) / (4 sec)
Acceleration = (8/4) (m/s²)
<em>Acceleration = 2 m/s²</em>
Answer:
average speed is 60km/h
Explanation:
you sum up the speed attained in each distance covered and divide it by 2 to get your answer
Answer:
his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph
Explanation:
Let say the speed of the bicycle while he moves towards the city is "v"
now the speed of the round trip must be smaller by 1 mph
so its speed for round trip will be

now we know that total time of the motion is 19 hr
so we will have


so we will have




by solving above equation we have

so his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph
Answer:
(B) 13.9 m
(C) 1.06 s
Explanation:
Given:
v₀ = 5.2 m/s
y₀ = 12.5 m
(A) The acceleration in free fall is -9.8 m/s².
(B) At maximum height, v = 0 m/s.
v² = v₀² + 2aΔy
(0 m/s)² = (5.2 m/s)² + 2 (-9.8 m/s²) (y − 12.5 m)
y = 13.9 m
(C) When the shell returns to a height of 12.5 m, the final velocity v is -5.2 m/s.
v = at + v₀
-5.2 m/s = (-9.8 m/s²) t + 5.2 m/s
t = 1.06 s
The centripetal acceleration is given by

where v is the tangential speed and r the radius of the circular orbit.
For the car in this problem,

and r=40 m, so we can re-arrange the previous equation to find the velocity of the car: