Answer:
"Right Hand
Right Hand Rule: Magnetic fields exert forces on moving charges. This force is one of the most basic known. The direction of the magnetic force on a moving charge is perpendicular to the plane formed by v and B and follows right hand rule–1 (RHR-1) "
Explanation:
The answer is c. +2.0 µC
To calculate this, we will use Coulomb's Law:
F = k*Q1*Q2/r²
where F is force, k is constant, Q is a charge, r is a distance between charges.
k = 9.0 × 10⁹ N*m/C²
It is given:
F = 7.2 N
d = 0.1 m = 10⁻¹ m
Q1 = -4.0 µC = 4 * 1.0 × 10⁻⁶ = 4.0 × 10⁻⁶
Q2 = ?
Thus, let's replace this in the formula for the force:
7.2 = 9.0 × 10⁹ * 4.0 × 10⁻⁶ * Q2/(10⁻¹)²
7.2 = 9 * 4 * 10⁹⁻⁶ * Q2/10⁻¹°²
7.2 = 36 × 10³ * Q2 / 10⁻²
Multiply both sides of the equation by 10⁻²:
7.2 × 10⁻² = 36 × 10³ * Q2
⇒ Q2 = 7.2 × 10⁻² / 36 × 10³ = 7.2/36 × 10⁻²⁻³ = 0.2 × 10⁻⁵ = 2 × 10⁻⁶
Since µC = 1.0 × 10^-6:
Q2 = 2 * 1.0 × 10^-6 = 2 µC
Answer:
When an object is immersed in water. it is pulled downwards due to gravitational pull of earth. Water exerts upward force on the object. This makes object rise up. This upward force is called buoyancy or upthrust.