The speed of light : 299 792 458 m / s
Q: Two charges q1 and q2, that are distance d apart , repel each other with a force of 6.40 N. what would be the force between two charges q1'=2q1 and q2'=3q2 that that are distance d apart?
Answer:
The force = 38.4 N
Explanation:
From coulombs law,
F = kq₁q₂/r² ............................ Equation 1
Where F = Force of attraction or repulsion between the charges, q₁ and q₂ = first and second charge respectively, r = distance between the charges, k = constant of proportionality.
When, F = 6.4 N, r = d m.
6.4 = kq₁q₂/d²......................... Equation 1
When q₁' = 2q₁, q₂' = 3q₂, r = d cm
F = k(2q₁)(3q₂)/d²
F = 6kq₁q₂/d².......................... Equation 2
Dividing Equation 1 by equation 2
6.4/F = kq₁q₂/d²/(6kq₁q₂/d²)
6.4/F = 1/6
F = 6.4×6
F = 38.4 N.
Thus the force = 38.4 N
Place the object in between the two jaws such that they touch opposite ends of the object making sure the object is held firmly but don’t press too tight. If you need to measure an internal diameter, then insert the upper jaws in to the cavity and open them till they touch the sides. Tighten the locking screw to hold the jaws in position.
Note the position of the vernier scale zero on the main scale. The main scale reading is the division just before where the zero mark of the vernier scale is aligned. So is the zero mark aligns just after the fifth division between 3 and 4 the main scale reading is then 3.5.
The next step is to take the vernier scale reading. To do this find the mark on the vernier scale which lines up perfectly with a mark on the main scale. The vernier reading can then be found by multiplying the least value of the vernier scale with the number of divisions till that mark. For example if the least value is 0.01 mm and the 7thmark of the vernier scale is lined up perfectly then the vernier scale reading is 7 x 0.01 = 0.07.
The final step is to add the main scale and vernier readings to get the final measurement. For example 3.5 + 0.07 = 3.57 mm.
D) Kilograms is the standard unit of mass
Answer:
Explanation:
Let the potential difference between the middle point and one of the plate be ΔV .
electric potential energy will be lost and it will be converted into kinetic energy .
Electrical potential energy lost = Vq , where q is charge on charge particle .
For proton
ΔV× q = 1/2 M V² ( kinetic energy of proton )
where M is mass and V be final velocity of proton .
For electron
ΔV× q = 1/2 m v² ( kinetic energy of electron )
where m is mass and v be final velocity of electron . Charges on proton and electron are same in magnitude .
As LHS of both the equation are same , RHS will also be same . That means the kinetic energy of both proton and electron will be same
1/2 M V² = 1/2 m v²
(V / v )² = ( m / M )
(V / v ) = √ ( m / M )
In other words , their velocities are inversely proportional to square root of their masses .
