A boat of mass 225 kg drifts along a river at a speed of 21 m/s to the west. what impulse is required to decrease the speed of t
2 answers:
The impulse required to decrease the speed of the boat is equal to the variation of momentum of the boat:
where
m=225 kg is the mass of the boat
is the variation of velocity of the boat
By substituting the numbers into the first equation, we find the impulse:
and the negative sign means the direction of the impulse is against the direction of motion of the boat.
where
m=225 kg is the mass of the boat
By substituting the numbers into the first equation, we find the impulse:
and the negative sign means the direction of the impulse is against the direction of motion of the boat.
You might be interested in
Explanation:
It is given that,
The acceleration of a particle, (negative as the particle is decelerating)
Initial distance, x₁ = 20 m
Initial time, t₁ = 4 s
New distance x₂ = 4 m
Velocity, v = 10 m/s
(A) Calculating initial distance using second equation of motion as :
u = 21 m/s
When velocity of the particle is zero, time taken is t (say). Using first equation of motion as :
t = 2.62 seconds
So, the velocity of the particle is zero at t = 2.62 seconds.
(B) Velocity at t = 11 s
v = 13 m/s
Total distance covered at t = 11 s. The overall path travelled by the particle during its entire journey is called total distance covered.
d = 132.48 m
So, the distance travelled by the particle at t = 11 seconds is 132.48 meters.