Answer:
2.295 eV
Explanation:
maximum wavelength, λ = 542 nm = 542 x 10^-9 m
The work function of the metal is defined as the minimum amount of energy falling on the metal so that the photo electrons just ejects the surface of metal.

where, h is the Plank's constant and c be the speed of light
h = 6.634 x 10^-34 Js
c = 3 x 10^8 m/s


Wo = 2.295 eV
Thus, the work function of this metal is 2.295 eV.
C.
Explanation: ionic compounds are metals and nonmetals, refer to your periodic table
The inflated balloon shrinks when it is placed in an ice bath with no change in atmospheric pressure.
<u>Explanation:</u>
When the inflated balloon is subjected to an ice bath, it shrinks. This is due to the fact that smaller volume gets occupied by the air/gas inside the balloon as the temperature decreases. Hence, causes the balloon walls to collapse.
An ice bath also lowers the overall air temperature of the balloon inside. As the temperature decreases, the air molecules move more slowly and with lower energy. Because of the particle's lower energy, their collisions with the walls are not enough to keep the inflated balloon.
Force exerted by Justin=300 N
Here power= 600 W
distance traveled=10 m
time=5 s
power is given by P= Work done/ time
600=work/5
so work= 60x5=3000J
now work done= force* distance
3000=F *10
F= 3000/10
F=300 N
The correct option is SCALE.
This is because the experimental data you are interested in is mass and scale is the instrument that is used to measure mass. To use the scale, measure the mass of your water before you put it inside the sun and measure the mass again after you remove it from the sun. The difference in mass is the quantity of water that is evaporated.
There are different type of scale and the one that you use will depend on the size of the material that you want to measure.<span />