"Electrostatic forces are attractive or repulsive forces between particles that are caused by their electric charges."
Answer:
Explanation:
Given
time of contact between bat and ball is 
suppose u is the incoming velocity and v is the final velocity after collision

Impulse exerted is given by change in momentum of the particle.
Initial momentum 
Final momentum 
Change in momentum 
Impulse 


Answer:
Minimum number of photons required is 1.35 x 10⁵
Explanation:
Given:
Wavelength of the light, λ = 850 nm = 850 x 10⁻⁹ m
Energy of one photon is given by the relation :
....(1)
Here h is Planck's constant and c is speed of light.
Let N be the minimum number of photons needed for triggering receptor.
Minimum energy required for triggering receptor, E₁ = 3.15 x 10⁻¹⁴ J
According to the problem, energy of N number of photons is equal to the energy required for triggering, that is,
E₁ = N x E
Put equation (1) in the above equation.

Substitute 3.15 x 10⁻¹⁴ J for E₁, 850 x 10⁻⁹ m for λ, 6.6 x 10⁻³⁴ J s for h and 3 x 10⁸ m/s for c in the above equation.

N = 1.35 x 10⁵
Answer:
μ = 0.6
Explanation:
given,
speed of car = 29.7 m/s
Radius of curve = 50 m
θ = 30.0°
minimum static friction = ?
now,
writing all the forces acting along y-direction
N cos θ - f sinθ = mg
N cos θ -μN sinθ = mg

now, writing the forces acting along x- direction
N sin θ + f cos θ = F_{net}
N cos θ + μN sinθ = F_{net}

taking cos θ from nominator and denominator




now, inserting all the given values

μ = 0.6