Answer:
0J
Option: B
Explanation:
Work is done when something is moved by the force in the direction of the force. That is the force (e.g., the weight) and the direction the object moves must be aligned for work to be done. In this given condition, the direction is horizontal and the force is downward as its gravity force. That 90° between the two vectors.
The work function is W = m × g ×h × cosθ

Hence,
Work done = 7 × 9.8 × 1.5 × cos(90)
Work done = 0 (cos
= 0)
Work done = 0
Therefore work done is 0 J.
Answer:
VAB = 20km/hr
Explanation:
<u>Given the following data;</u>
Velocity of car A, VA = 60km/hr
Velocity of car B, VB = 80km/hr
To find the relative velocity of B w.r.t A, VAB;
Since the two cars are moving in the same direction, we have;
VAB = VB - VA
Substituting into the equation, we have;
VAB = 80 - 60
<em>VAB = 20km/hr</em>
Therefore, the relative velocity of car B with respect to car A is 20 kilometers per hour.
Answer:
10 km/hr/s
Explanation:
The acceleration of an object is given by

where
v is the final velocity
u is the initial velocity
t is the time
For the car in this problem:
u = 0

t = 6 s
Substituting in the equation,

<em>Answer:</em>
<em>Velocity is vector quantity.So it needs direction in addition to speed.</em>
<em>Explanation:</em>
<em>The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of its speed and direction of motion. </em>