Answer:
a)= 98kJ
b)=108kJ
c) = 10kJ
Explanation:
a. The work that is done by gravity on the elevator is:
Work = force * distance
= mass * gravity * distance
= 1000 * 9.81 * 10
= 98,000 J
= 98kJ
b)The net force equation in the cable
T - mg = ma
T = m(g+a)
T = 1000(9.8 + 10)
T = 10800N
The work done by the cable is
W = T × d
= 10800N × 10
= 108000
=108kJ
c) PE at 10m = 1000 * 9.81 * 10 = 98,100 J
Work done by cable = PE +KE
108,100 J = KE + 98,100 J
KE = 10,000 J
= 10kJ
=
Answer:
The Flemings left hand rule is used to find the magnitude of a magnetic force
Explanation:
Fleming's left hand rule states that if the first three fingers are held mutually at right angles to one another, then the fore finger points into the direction of magnetic field the middle finger in the direction of current while the thumb points in the direction of force.
Mathematically
Magnetic Force F= BILsinθ
Where
B= magnetic field density Tesla
I= current
L= length of conductor
θ= angle of conductor with field
The appropriate expression for the calculation of power by relating the angular energy in a given time.
In other words the instantaneous power of an angular accelerating body is the torque times the angular velocity

Where
Torque
Angular speed
Our values are given by


The angular velocity must be transformed into radians per second then


Replacing,



The average power delivered by the engine at this rotation rate is 211.1kW
Answer:
The correct answer is A. The sun is the energy source of the surface currents in the ocean
Answer:
yes; yes
Explanation:
Phases of the moon refers to the shapes of the moon due to the lit part of it visible from the Earth. On a new moon day, the moon comes between the sun and the earth such that the lit portion is not visible from the Earth. On a full moon day, the earth comes between the sun and the moon and the whole lit part is visible.
When one would view the earth from the moon, the earth would also be visible as going through the phases. The order would be reversed. Understand this with the following example, On a new moon day, the Earth would be visible completely lit from the moon. So it will be full Earth day on the moon. On a full moon day, the lit side of the Earth would be completely away and hence, from the moon, new earth would be there.