A: 0.7 -0.8 and 0hrs
B: 0.2 - 0.4 and 1.0 -1.1 hrs
C: 0-0.2 hrs and 0.8 - 1.0 hrs
D: 0.4 - 0.7 hrs
Answer:
(a) Jx = -1.14Ns, Jy = 110×3×10-³ = 0.330Ns (b) V = (0m/s)ı^−(1.79m/s)ȷ^
Explanation:
Given
W = 0.56N = mg
m = 0.56/g = 0.56/9.8 = 0.057kg
t = 3.00ms = 3.00×10-³s
Impulse is a vector quantity so we would treat it as such
We have been given the force and velocity in their component forms so to get the impulse from these quantities, we pick the respective component for the quantity we want to calculate and do the necessary calculation. The masses are scalar quantities and so do not affect the signs used in the calculations whether positive or negative. So we have that
u = (20.0m/s)ı^−(4.0m/s)ȷ^
ux = 20m/s
uy = – 4.0m/s
F = – (380N)ı^+(110N)ȷ^
Fx = –380N
Fy = 110N
J = impulse = force × time = F×t
So Jx = Fx ×t
Jy = Fy×t
Jx = –380×3×10-³ = -1.14Ns
Jy = 110×3×10-³ = 0.330Ns
Impulse also equals the change in momentum of the body. So
J = m(v–u)
J/m = v – u
V= J/m + u
Vx = Jx/m + ux
Vx = –1.14/0.057 + 20
Vx = -20 + 20 = 0m/s
Vx = 0m/s
Vy= Jy/m + uy
Vy= 0.33/0.057 + (-4.0)
Vy= 5.79 + (-4.0) = 1.79m/s
V = (0m/s)ı^−(1.79m/s)ȷ^
As per Newton's II law we know that

here F = force applied
m = mass of object = 2 kg
a = acceleration = 2 m/s^2
now as per above formula we will have


so here applied force on the ball will be 4 N
Electromagnetic waves going through outer space has the greatest speed among all kind of waves.
Option B
<u>Explanation</u>:
Electromagnetic waves are the waves that can go through the vaccum of space. Electromagnetic waves are made by the vibration of an electric charge. This vibration makes a wave that has both an "electric and magnetic nature". An electromagnetic wave transfers energy through a vaccum at a speed of
(speed esteem ordinarily depicted by the sign c). The spread of an electromagnetic wave through a material medium happens at a net speed which is under
.