If F =m*a
and the question says how much force the s needed to accelerate a 68kg skier to a rate of 1.2ms^-2
Then F = 68*1.2
Answer:
A) ( - 200t + 40 ) volts
B) b) anticlockwise , c) anticlockwise , d) clockwise , e) clockwise
Explanation:
Given data:
magnetic flux (Φm) = 5.0t^2 − 2.0t
number of turns = 20
<u>a) determine induced emf </u>
E = - N 
= - N ( 10t - 2 ) = - 20 ( 10t - 2 )
= - 200t + 40 volts
<u>b) Determine direction of induced current </u>
i) at t = 0
E = - 0 + 40 ( anticlockwise direction )
ii) at t = 0.10
E = -20 + 40 = 20 ( anticlockwise direction )
iii) at t = 1
E = - 200 + 40 = - 160 ( clockwise direction)
iv) at t = 2
E = -400 + 40 = - 360 ( clockwise direction )
Answer:
Answer in Explanation
Explanation:
Whenever we talk about the gravitational potential energy, it means the energy stored in a body due to its position in the gravitational field. Now, we know that in the gravitational field the work is only done when the body moves vertically. If the body moves horizontally on the same surface in the Earth's Gravitational Field, then the work done on the body is considered to be zero. Hence, the work done or the energy stored in the object while in the gravitational field is only possible if it moves vertically. This vertical distance is referred to as height. <u>This is the main reason why we require height in the P.E formula and calculations.</u>
The derivation of this formula is as follows:
Work = Force * Displacement
For gravitational potential energy:
Work = P.E
Force = Weight = mg
Displacement = Vertical Displacement = Height = h
Therefore,
P.E = mgh
Answer: only the third option. [Vector A] dot [vector B + vector C]
The dot between the vectors mean that the operation to perform is the "scalar product", alson known as "dot product".
This operation is only defined between two vectors, not one scalar and one vector.
When you perform, in the first option, the dot product of any ot the first and the second vectors you get a scalar, then you cannot make the dot product of this result with the third vector.
For the second option, when you perform the dot product of vectar B with vector C you get a scalar, then you cannot make the dot product ot this result with the vector A.
The third option indicates that you sum the vectors B and C, whose result is a vector and later you make the dot product of this resulting vector with the vector A. Operation valid.
The fourth option indicates the dot product of a scalar with the vector A, which we already explained that is not defined.
