Answer:
The arrow is at a height of 500 feet at time t = 2.35 seconds.
Explanation:
It is given that,
An arrow is shot vertically upward at a rate of 250 ft/s, v₀ = 250 ft/s
The projectile formula is given by :

We need to find the time(s), in seconds, the arrow is at a height of 500 ft. So,

On solving the above quadratic equation, we get the value of t as, t = 2.35 seconds
So, the arrow is at a height of 500 feet at time t = 2.35 seconds. Hence, this is the required solution.
Answer:
Explanation:
Given that,
Initial speed of the girl is
u = 1.4m/s
Height she is going is
H = 2.45m
Incline plane she will pass to that height
L = 12.4m
Mass of girl and bicycle is
M=60kg
Frictional force that oppose motion is
Fr = 41N
Speed at lower end of inclined plane
V2 = 6.7m/s
Work done by the girl when the car travel downward
Using conservation of energy
K.E(top) + P.E(top) + work = K.E(bottom) + P.E(bottom) + Wfr
Where Wfr is work done by friction
Wfr = Fr × d
P.E(bottom) is zero, sicne the height is zero at the ground
K.E is given as ½mv²
Then,
½M•u² + MgH + W = ½M•V2² + 0 + Fr×d
½ × 60 × 1.4² + 60×9.8 × 2.45 + W = ½ × 60 × 6.7² + 41 × 12.4
58.8 + 1440.5 + W = 1855.1
W = 1885.1 —58.8 —1440.5
W = 355.8 J
There are no natural forces mentioned on the list you've provided.
Answer:
0N.
Explanation:
Net force is the sum total of forces acting on an object.
The Fn which is the net force is
450+ (-250) + (-600)+ 600+ 0 + 250 + (-450)
= 450-250+(-600)+ 600+0+250-450
= 0N
The net force is 0
Answer:
0 m/s^2
Explanation:
Acceleration is the change in velocity / time
=> In this case there isn't any change in velocity
=> It is = to 0.