Answer:
A. Power = Work / Time
Explanation:
Power is the amount of work done over time, or rather the rate of work, which is given by the unit of watts (W). Since work is defined by Force * Displacement, we can also say Power = Force * Displacement / Time.
Answer:
q = 3.6 10⁵ C
Explanation:
To solve this exercise, let's use one of the consequences of Gauss's law, that all the charge on a body can be considered at its center, therefore we calculate the electric field on the surface of a sphere with the radius of the Earth
r = 6 , 37 106 m
E = k q / r²
q = E r² / k
q =
q = 4.5 10⁵ C
Now let's calculate the charge on the planet with E = 222 N / c and radius
r = 0.6 r_ Earth
r = 0.6 6.37 10⁶ = 3.822 10⁶ m
E = k q / r²
q = E r² / k
q =
q = 3.6 10⁵ C
Most likely B. Will erode, if not it will grow weeds
The car should have a velocity of 60 m/s to attain the same momentum as that of the truck of 2000 kg.
Answer:
Explanation:
Momentum is measured as the product of mass of object with the velocity attained by that object.
Momentum of 2000 kg truck = Mass × Velocity
Momentum of 2000 kg truck = 2000×30 = 60000 N
Similarly, the momentum of 1000 kg car will be 1000× velocity of the 1000 kg car.
Since, it is stated that momentum of 2000 kg truck is equal to the momentum of 1000 kg of car, then the velocity of 1000 kg of car can be determined by equating the momentum of car and truck.
Momentum of 2000 kg truck = Momentum of 1000 kg car
60000=1000×velocity of 1000 kg car
Velocity of 1000 kg car = 60000/1000=60 m/s
So, the car should have a velocity of 60 m/s to attain the same momentum as that of the truck of 2000 kg.
Light waves are reflected from front and back surfaces of the thin films and constructive interference between the two reflected waves occurs in different places for different wavelengths. Light shining on the upper surface of the thin film with thickness t is partly reflected at the upper surface (path abc). Light transmitted from the upper surface is partly reflected at the lower surface (path abdef). The two reflected waves come together at point P on the retina of the eye. Depending on the phase relationship, they may interfere constructively or destructively. Different colors have different wavelengths, so the interference may be constructive for some colors and destructive for others.