Explanation:
When there is no change in chemical composition of a substance then it is known as physical change.
When we say that mass is conserved during a physical change then it means that total mass of the substance or object will remain the same from beginning till the end.
For example, a metal box of mass 20 grams is beaten with hammer. Its shape will change which is a physical change and after beaten with the hammer its mass still remains 20 grams.
Answer:
The charge on the ball bearing 4.507 × 10^-8 C
Explanation:
From Coulomb's law
F = kq1q2/r²
make q2 the subject
q2 = Fr²/kq1
q2 = (1.8×10^-2 × 0.026²) ÷ (9×10^9 × 30×10^-9)
q2 = 4.507 × 10^-8 C
Answer:
Height of the rocket be one minute after liftoff is 40.1382 km.
Explanation:

v = velocity of rocket at time t
g = Acceleration due to gravity =
= Constant velocity relative to the rocket = 2,900m/s.
m = Initial mass of the rocket at liftoff = 29000 kg
r = Rate at which fuel is consumed = 170 kg/s
Velocity of the rocket after 1 minute of the liftoff =v
t = 1 minute = 60 seconds'
Substituting all the given values in in the given equation:


Height of the rocket = h



Height of the rocket be one minute after liftoff is 40.1382 km.
Answer:
Flux is 21 Nm^2/C.
Explanation:
Electric field, E = 6 N/C along X axis
Electric filed vector, E = 6 i N/C
Area, A = 4 square meter
Area vector

The flux is given by
