Answer:
A. Light acts as particles, causing electrons on the surface it strikes to be destroyed.
Explanation:
- The photoelectric effect is a phenomenon that occurs when light shined onto a metal surface causes the ejection of electrons from that metal. It was observed that only certain frequencies of light are able to cause the ejection of electrons.
Answer:
i think its B sorry if its wrong
Working...
length of wire L = 1.5 m
current I = 7 A
potential difference V = 68 Volt
According to Ohm's Law
V = IR
R = V/I
R = 68/7
R = 9.7 Ω
Answer:
8000J
Explanation:
The kinetic energy of the car lost during breaking are converted to thermal energy and are gained by the brakes.
Kinetic energy loss by car = thermal energy gained by brakes.
∆K.E = ∆T.E ....1
The Kinetic energy loss by car can be expressed as;
∆K.E = K.E1 - K.E2
Initial K.E = K.E1 = 10000J
Final K.E = K.E2 = 2000J
∆K.E= 10000J - 2000J = 8000J
From equation 1,
∆K.E = ∆T.E
∆T.E = 8,000J
thermal energy gain by brakes = 8,000J
Answer:
A
Explanation:
because the speed divide by the frequency is equal to the wavelength(in meters)
5×10² m