Answer: The velocity at different marked time points are given as
t1 = -
t2 = +
t3 = +
t4 = -
t5 = 0
Explanation:
The slope of the tangent of the curve indicates the instantaneous velocity. So if the slope of the tangent is positive, that Is, the tangent makes a positive angle (above the horizontal axis) with the horizontal
axis, then the velocity at this point is positive, and if the slope of the tangent is negative, that is the tangent makes a negative angle with the horizontal axis (below the horizontal axis), then the velocity at this point is negative.
When the tangent of the line is parallel to the horizontal axis, the velocity is 0.
From the position-time graph attached, the sign on the instantaneous velocity for each time marked on the graph is given below
t1 = -
t2 = +
t3 = +
t4 = -
t5 = 0
QED!
Answer:
240 ohms
Explanation:
From Ohms law we deduce that V=IR and making R the subject of the formula then R=V/I where R is resistance, I is current and V is coltage across. Substituting 120 V for V and 0.5 A for A then
R=120/0.5=240 Ohms
Alternatively, resistance is equal to voltage squared divided by watts hence 
Answer:
<em>W=700 Joule</em>
Explanation:
<u>Physics Work
</u>
Is the dot product of the force vector by the displacement vector
When both the force and the displacements are pointed in the same direction, the formula reduces to its scalar version
The weightlifter is applying a net force of 350 N to lift the weights a distance of 2 m, thus the net work done is
Explanation:
A student solving for the acceleration of an object has applied appropriate physics principles and obtained the expression :
Where
m = 7 kg
So, the correct step for obtaining a common denominator for the two fractions in the expression in solving for a is (a) and the value of a is :
Hence, the correct option is (a).
