Answer:
Option d and e are correct.
Explanation:
The expression for velocity of pulse in a stretched string can be given as follows
v = 
where T is tension in the string , m is mass of string per unit length.
Use of lighter string of the same length, under the same tension amounts to higher m so velocity will decrease. Hence option d is correct.
Similarly, v is directly proportional to square root of tension. So if we increase tension , velocity also increases. So option e ) is correct.
Answer:
Open
Closed
Explanation:
An open circuit is an electrical circuit in which the electric current does not circulate because it is interrupted or not communicated by means of an electrical conductor. While in a closed circuit, the current, that is the flow of electrons, travels from the beginning of the circuit to the end.
Answer:
The critical angle for light is 41.81 degrees.
Explanation:
We have, light is propagating from a material with index of refraction of 1.50 to a material with index of refraction of 1. It is required to find the critical angle for light. It is angle for which the angle of refraction is equal to 90 degrees. It is given by :
So, the critical angle for light is 41.81 degrees.
