Explanation:
13 cmHg (centimeters of mercury) is the pressure at the bottom of a column of mercury 13 cm deep. It is the equivalent of about 17.3 kPa or 2.5 psi.
Answer:
The total energy of the composite system is 7.8 J.
Explanation:
Given that,
Height = 0.15 m
Radius of circular arc = 0.27 m
Suppose, the entire track is friction less. a bullet with a m₁ = 30 g mass is fired horizontally into a block of wood with m₂ = 5.29 kg mass. the acceleration of gravity is 9.8 m/s.
Calculate the total energy of the composite system at any time after the collision.
We need to calculate the total energy of the composite system
Total energy of the system at any time = Potential energy of the system at the stopping point


Put the value in to the formula


Hence, The total energy of the composite system is 7.8 J.
The energy carried by the incident light is

where h is the Planck constant and f is the frequency of the light. The threshold frequency is the frequency that corresponds to the minimum energy needed to eject the electrons from the metal, so if we substitute the threshold frequency in the formula, we get the minimum energy the light must have to eject the electrons: