Answer:
W = 166422.729 N
Explanation:
given,
diameter of the balloon = 30 m
density of the air = 1.10 Kg/m³
weight of the balloon and cargo = ?
density of the surrounding air = 1.20 kg/m³
we know,
Density = mass/volume
m = density x volume


m = 16964.6 Kg
Weight of the balloon
W = m g
W = 16964.6 x 9.81
W = 166422.729 N
Weight of the balloon and the cargo is equal to W = 166422.729 N
I have no idea what that is, but all of your answers right
Answer:

Explanation:
Given that,
Magnetic force acting on an electron, 
The magnitude of the magnetic field,
We need to find the magnitude of the velocity. We know that the magnetic force is given by :

Where
v is the velocity
So,

So, the magnitude of velocity is
.
Answer:
s = 90 m
a = 56 m/s²
Explanation:
I will ASSUME that your equation is silly as it reduces to V = 11t which is constant, and that you mean V = 9t² + 2t
Position is the integral of differential velocities
s = 
s = 3t³ + t² | from 0 to 3
s = 3(3)³ + 3² - (0) = 90 m
acceleration is the derivative of velocity
a = v' = 18t + 2
a(3) = 18(3) + 2 = 56 m/s²