Impulse = (force) x (length of time the force lasts)
I see where you doodled (60)(40) over on the side, and you'll be delighted
to know that you're on the right track !
Here's the mind-blower, which I'll bet you never thought of:
On a force-time graph, impulse (also change in momentum)
is just the <em>area that's added under the graph during some time</em> !
From zero to 60, the impulse is just the area of that right triangle
under the graph. The base of the triangle is 60 seconds. The
height of the triangle is 40N . The area of the triangle is not
the whole (base x height), but only <em><u>1/2 </u></em>(base x height).
1/2 (base x height) = 1/2 (60s x 40N) = <u>1,200 newton-seconds</u>
<u>That's</u> the impulse during the first 60 seconds. It's also the change in
the car's momentum during the first 60 seconds.
Momentum = (mass) x (speed)
If the car wasn't moving at all when the graph began, then its momentum is 1,200 newton-sec after 60 seconds. Through the convenience of the SI system of units, 1,200 newton-sec is exactly the same thing as 1,200 kg-m/s . The car's mass is 3 kg, so after 60 sec, you can write
Momentum = M x V = (3 kg) x (speed) = 1,200 kg-m/s
and the car's speed falls right out of that.
From 60to 120 sec, the change in momentum is the added area of that
extra right triangle on top ... it's 60sec wide and only 20N high. Calculate
its area, that's the additional impulse in the 2nd minute, which is also the
increase in momentum, and that'll give you the change in speed.
initial velocity of the car given as
final velocity is given as
as we know that
now we can convert final speed into m/s
now acceleration is rate of change in velocity
so the acceleration of the car is 3 m/s^2
The Right Answer Is: <span>the high frequencies and shorter wavelengths penetrates body easily.</span>
Answer:
initial velocity=12.31 m/s
Final speed= 16.234 m/s
Explanation:
Given Data
height=5.72 m
distance=13.30 m
To Find
Initial Speed=?
Solution
Use the following equation to determine the time of the stone is falling.
d = vi ×t ½ ×9.8 × t²
Where
d = 5.72m and vi = 0 m/s
so
5.72 = ½× 9.8 ×t²
t = √(5.72 ÷ 4.9)
t=1.08 seconds
To determine the initial horizontal velocity use the following equation.
d = v×t
13.30 = v ×1.08
v = 13.30 ÷ 1.08
v=12.31 m/s
To determine stone’s final vertical velocity use the following equation
vf = vi+9.8×t............vi=0 m/s
vf = 9.8×1.08
vf= 10.584 m/s
To determine stone’s final speed use the following equation
Final speed = √[Horizontal velocity²+Final vertical velocity²]
Final speed = √{(12.31 m/s)²+(10.584 m/s)²}
Final speed= 16.234 m/s
