The initial kinetic energy of the boat and its rider is
After Sam stops it, the final kinetic energy of the boat+rider is
because its final velocity is zero.
For the law of conservation of energy, the work done by Sam is the variation of kinetic energy of the system:
where the negative sign is due to the fact that the force Sam is applying goes against the direction of motion of the boat.
Hi there!
We can calculate linear momentum using the following:
p = linear momentum (kgm/s)
m = mass (kg)
v = velocity (m/s)
Calculate:
Now, we can relate force, time, and momentum with the following:
I = Impulse (kgm/s)
F = Force (N)
t = time (s)
Rearrange to solve for force:
The impulse is equal to the change in momentum. Since the car comes to a halt, all of its momentum is lost, so:
Solve:
**Negative force since the positive direction is towards the wall, and the negative direction is away from the wall.
The time of flight depends only on the initial velocity and the initial height
Explanation:
An object is said to be in free fall if the only force acting on it is the force of gravity. If this is the case, then the motion of the object in free fall is a uniformly accelerated object, with constant acceleration towards the ground. The time of flight can be found by using the suvat equation:
where
s is the displacement (which corresponds to the initial height of the object)
u is the initial vertical velocity
is the acceleration
t is the time of flight
Therefore, from the equation, we see that the time of flight depends only on two factors:
- s, the initial height of the object
- u, its initial velocity
In case the air resistance is not negligible, then the acceleration is no longer constant, and the time of the fall also depends on other factors such as the mass of the object and its shape, which affects the magnitude of the air resistance acting on the body.
Learn more about free fall:
brainly.com/question/1748290
brainly.com/question/11042118
brainly.com/question/2455974
brainly.com/question/2607086
#LearnwithBrainly
Answer:
a) t = 0.0185 s = 18.5 ms
b) T = 874.8 N
Explanation:
a)
First we find the seed of wave:
v = fλ
where,
v = speed of wave
f = frequency = 810 Hz
λ = wavelength = 0.4 m
Therefore,
v = (810 Hz)(0.4 m)
v = 324 m/s
Now,
v = L/t
where,
L = length of wire = 6 m
t = time taken by wave to travel length of wire
Therefore,
324 m/s = 6 m/t
t = (6 m)/(324 m/s)
<u>t = 0.0185 s = 18.5 ms</u>
<u></u>
b)
From the formula of fundamental frquency, we know that:
Fundamental Frequency = v/2L = (1/2L)(√T/μ)
v = √(T/μ)
where,
T = tension in string
μ = linear mass density of wire = m/L = 0.05 kg/6 m = 8.33 x 10⁻³ k gm⁻¹
Therefore,
324 m/s = √(T/8.33 x 10⁻³ k gm⁻¹)
(324 m/s)² = T/8.33 x 10⁻³ k gm⁻¹
<u>T = 874.8 N</u>