Answer:
0.75 NC⁻¹
Explanation:
Electric field intensity ( or strength of the electric field ) is the force per a 1 C charge,
So, Force (F) = Electric field intensity(E) × Charge (q)
F = E×q ⇒ q = F/E
= 4.5×10⁻⁴/6×10⁻⁴ = 0.75 NC⁻¹
According to cool om's law electric fields are generated due to charges. When charges are same there is a repulsive force acted on both charges. When charges are opposite there is a attraction force acted on both charges.
According to cool om's law,
F =G×q1×q2 / r²
F = force exerted of two charges
q1 , q2 = charges
r = distance between two charges
And also Electric field intensity is a vector which has a magnitude and direction both. Direction is depending on a charge and the sign of the charge
Answer:
7 seconds
Explanation:
he went down -28 m/s so 7 times -4 equals -28 m/s which is what he needed to slowness down to 10 m/s
Franklin had been waiting for an opportunity like this. He wanted to demonstrate the electrical nature of lightning, and to do so, he needed a thunderstorm.
He had his materials at the ready: a simple kite made with a large silk handkerchief, a hemp string, and a silk string. He also had a house key, a Leyden jar (a device that could store an electrical charge for later use), and a sharp length of wire. His son William assisted him.
Franklin had originally planned to conduct the experiment atop a Philadelphia church spire, according to his contemporary, British scientist Joseph Priestley (who, incidentally, is credited with discovering oxygen), but he changed his plans when he realized he could achieve the same goal by using a kite.
Answer:
Em₀ = 245 J
Explanation:
We can solve this problem with the concepts of energy conservation, we assume that there is no friction with the air.
Initial energy the highest point
Em₀ = U
Em₀ = m g h
The height can be found with trigonometry
The length of the pendulum is L and the length for the angle of 60 ° is L ’, therefore the height from the lowest point is
h = L - L’
cos θ = L ’/ L
L ’= L cos θ
h = L (1 - cos θ)
We replace
Em₀ = m g L (1- cos θ)
Let's calculate
Em₀ = 10 9.8 5.0 (1 - cos 60)
Em₀ = 245 J
