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
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
Answer:
The impulse on the object is 60Ns.
Explanation:
Impulse is defined as the product of the force applied on an object and the time at which it acts. It is also the change in the momentum of a body.
F = m a
F = m(
)
⇒ Ft = m(
-
)
where: F is the dorce on the object, t is the time at which it acts, m is the mass of the object,
is its initialvelocity and
is the final velocity of the object.
Therefore,
impulse = Ft = m(
-
)
From the question, m = 3kg,
= 0m/s and
= 20m/s.
So that,
Impulse = 3 (20 - 0)
= 3(20)
= 60Ns
The impulse on the object is 60Ns.
Complete Question
A person throws a pumpkin at a horizontal speed of 4.0 m/s off a cliff. The pumpkin travels 9.5m horizontally before it hits the ground. We can ignore air resistance.What is the pumpkin's vertical displacement during the throw? What is the pumpkin's vertical velocity when it hits the ground?
Answer:
The pumpkin's vertical displacement is 
The pumpkin's vertical velocity when it hits the ground is 
Explanation:
From the question we are told that
The horizontal speed is 
The horizontal distance traveled is 
The horizontal distance traveled is mathematically represented as

Where t is the time taken
substituting values

=> 

Now the vertical displacement is mathematically represented as

now the vertical velocity before the throw is zero
So


Now the final vertical velocity is mathematically represented as

substituting values


A=m/s^2(meter per second square)
Work=joule