Answer:
Explanation:
In photoelectric effect , radiation of some energy is made to fall on metal plate which results in the ejection of electrons by the metal plate . The kinetic energy of electrons comes from the energy of radiation falling on metal plate . Some of energy of radiation falling on metal plate is used in the process of bringing the electron to the surface and it is called threshold energy . The radiation must have at least this energy to see to it that electrons are ejected . and the rest of the energy of radiation is used in imparting kinetic energy to the electron .
The red light radiation has least energy so it is least likely to eject electrons from metal plate and produce photoelectric effect .
Using p1v1/t1=p2v2/t2
p1=50
p2=225
v1=400ml
v2=?
t1=-20=253k
t2=60=333k
50x400/253=225xv2/333
7.9=0.7xv2
v2=7.9/0.7
v2=11.3ml
<span>a pure substance that can be separated into different elements by chemical means</span>
Answer:
Hi
Explanation:
That's why rubbing your hands together makes them warmer. ... Friction causes the molecules on rubbing surfaces to move faster, so they have more energy. This gives them a higher temperature, and they feel warmer. Heat from friction can be useful.