Answer:
The answer to your question is
a) t = 2.55 s
b) t = 5.5 s
Explanation:
Data
vo = 25 m/s
h = 2 m
g = 9.81 m/s
Formula
t = -(vo)/g
a)
t = -(25)/9.81
t = 2.55 s
b)
Tt = 2t
Tt = 2(2.55)
Tt = 5.1 s
Time in the last 10 m
10 = 25t + (1/2)(9.81)t²
Simplify
10 = 25t 4.91t²
4.9t² + 25t - 10 = 0
Solve the equation using an online calculator
t₁ = 0.37 s t₂ = -5.47 s
The correct answer is t₁, t₂ is incorrect because there are no negative answers.
Total time = 5.1 + 0.37
= 5.5 s
Answer:
61.22m
Explanation:
Maximum height in projectile is expressed as;
H = u²sin²θ/2g
u is the speed
g is the acceleration due to gravity
θ is the angle of projection
Substitute the given values into the formula;
H = u²sin²θ/2g
H = 40²sin²60/2g
H = 1600(0.8660)²/2(9.8)
H = 1600(0.8660)²/2(9.8)
H = 1,199.9/19.6
H = 61.22m
Hence the maximum height achieved by the ball is 61.22m
Well, Air resistance is a special type of friction (you cannot classify it in other categories). That force of air-resistance is often observed to oppose the motion of the object,( like every other frictional forces)
Hope this helps!
W = _|....F*dx*cos(a)........With F=force, x=distance over which force acts on object,
.......0.............................and a=angle between force and direction of travel.
Since the force is constant in this case we don't need the equation to be an integral expression, and since the force in question - the force of friction - is always precisely opposite the direction of travel (which makes (a) equal to 180 deg, and cos(a) equal to -1) the equation can be rewritted like so:
W = F*x*(-1) ............ or ............. W = -F*x
The force of friction is given by the equation: Ffriction = Fnormal*(coeff of friction)
Also, note that the total work is the sum of all 45 passes by the sandpaper. So our final equation, when Ffriction is substituted, is:
W = (-45)(Fnormal)(coeff of friction)(distance)
W = (-45)...(1.8N).........(0.92).........(0.15m)
W = ................-11.178 Joules