Answer:
A) 1.9m/s
Explanation:
Use the equation v=d/t
The time is 10 seconds. The distance is more complicated because it’s a circle so u use the equation for circumference C=2•pi•r. So you just do the circumference over time and get the answer. Hope this helps
Answer:
Less than.
Explanation:
We have the positive charged metal sphere and we have to determine the electric field at a point near to it. In order to find that if we bring the positive test charge at that point then as we know that "like charges repel" so their electric field lines will repel each other resulting in a weaker electric field.
However if we bring the negative test charge at that point then of course there will be attraction and also the the electric field lines will direct from the positive to negative resulting in a stronger electric field between them. So there will be larger electric field then before.
"In this case, It can be concluded that electric field will be less than it was at this point before the test charge was present."
Remember Coulomb's law: the magnitude of the electric force F between two stationary charges q₁ and q₂ over a distance r is

where k ≈ 8,98 × 10⁹ kg•m³/(s²•C²) is Coulomb's constant.
8.1. The diagram is simple, since only two forces are involved. The particle at Q₂ feels a force to the left due to the particle at Q₁ and a downward force due to the particle at Q₃.
8.2. First convert everything to base SI units:
0,02 µC = 0,02 × 10⁻⁶ C = 2 × 10⁻⁸ C
0,03 µC = 3 × 10⁻⁸ C
0,04 µC = 4 × 10⁻⁸ C
300 mm = 300 × 10⁻³ m = 0,3 m
600 mm = 0,6 m
Force due to Q₁ :

Force due to Q₃ :

8.3. The net force on the particle at Q₂ is the vector

Its magnitude is

and makes an angle θ with the positive horizontal axis (pointing to the right) such that

where we subtract 180° because
terminates in the third quadrant, but the inverse tangent function can only return angles between -90° and 90°. We use the fact that tan(x) has a period of 180° to get the angle that ends in the right quadrant.
Answer:
Specific gravity is 0.56
Explanation:
We know that
mass of water displaced by the wood is, m1( apparent mass when wood in air and lead is submerged in water) - m2(the apparent mass when wood and lead both are submerged in water)
= 0.0765 - 0.0452 = 0.0313 Kg
So the specific gravity of the wood is, = mass of wood / mass of water displaced by the wood
= 0.0175/0.0313
=0.56