U=70 , v= 0, t=35, a=?
v=u+at
0=70+a(35)
-70=35a
a=-2m/s^2
Decelerate 2ms^-2 or acceleration is -2ms^-2
Momentum is conserved throughout this scenario.
Before the man does anything, the total momentum of him and his book is zero. So we know that it'll be zero after he throws the book.
Momentum = (mass) x (velocity)
The man gives the book (1.2 kg)x(10 m/s north) = 12 kg-m/s north
of momentum.
Since the total momentum must be zero, the man himself picks up 120 kg-m/s of momentum south.
(his mass)x(his v) = 120 kg-m/s south = (770 kg-m/s^2/9.8 m/s^2)x(V).
His velocity southward = (120 x 9.8) / (770) m/s .
He needs to reach the shore 10m away.
Time = distance/speed
= (10 x 770) / (120 x 9.8) seconds
= 6.55 seconds
Answer:
2m/s^2
Explanation:
Clculate the acceleration:
V = u +at
20m/s = 0 + a*10s
a = 20m//10s
a = 2m/s²
From the data given , it is not possible to calculate the displacement , because no direction of motion is given
But it is possible to calculate the distance travelled
Distance = ut + ½ *a*t²
distance = 0 + ½ * 2m/s * 10²s
distance = 100m
The net force on the hanging object is zero. If it were not zero, then the object would be accelerating in some direction.
