Answer:
Moment is the product of force and its perpendicular distance from a point along its line of action.
The net moments on clockwise and anticlockwise is zero at a point.
The net force applied on a spanner handle is equal to the moment of the rotation
Answer: d)
Explanation: In order to justify the answer we have to consider that the energy of photons directely depent on the frequency so the energy is inverselly dependent of the wavelegth.
If both beams have the same power, this means Energy/time so the number of photons per second must be different. As consequence a) is wrong as b) since it is not posible since UV photon have more energy that IR photons. c) It is no necessary know the frequency since the wavelength is related in the form:
c=λν c is the speed of light, λ the wavelegth and ν the frequency.
d) Certainly will be more more IR photons than UV photons to get the same beam power.
Answer: I don't know this one but I'm just came here for points
Explanation:
Using Newton's second law of motion:
F=ma ; [ F = force (N: kgm/s^2);m= mass (kg); a = acceleration (m/s^2)
Given: Find: Formula: Solve for m:
F: 2500N mass:? F=ma Eq.1 m=F/a Eq. 2
a= 200m/s^2
Solution:
Using Eq.2
m= (2500 kgm/s^2)/ (200m/s^2) = 12.5 kg
The amount of heat needed to increase the temperature of a substance by

is given by

where m is the mass of the substance, Cs is its specific heat capacity and

is the increase of temperature.
If we re-arrange the formula, we get

And if we plug the data of the problem into the equation, we can find the specific heat capacity of the substance: