If satisfy the liner equation 3x + ky = 4
, find the value of k, Can there be more than one value of k?
From the choices given below, choose the equation whose graphs are given in Fig. (1) and Fig. (2).
For Fig. 1 For Fig. 2
(i) y = x (i) y = x + 2
(ii) x + y = 0 (ii) y = x – 2
(iii) y = 2x (iii) y = – x + 2
(iv) 2 + 3y = 7x (iv) x + 2y = 6
Fig. 1
Fig. 2
If the work done by a body on application of a constant force is directly proportional to the distance travelled by the body, express this in the form of an equation in two variables and draw the graph of the same by taking the constant force as 5 units. Also read from the graph the work done when the distance travelled by the body is
(i) 2 units (ii) 0 unit.
Let the work done by the constant force be y units and the distance travelled by the body be x units.
Constant force = 5 units
We know that
Work done = Force x Displacement
⇒ y = 5x
Table of solutions
X |
0 |
1 |
y |
0 |
5 |
We plot the points (0, 0) and (1, 5) on the graph paper and join the same by a ruler to get the line which is the graph of the equation y = 5x.
(i) Let A → (2, 0), Through A, draw a line parallel to OY to intersect the graph of the equation y = 5x at B. Through B, draw a line parallel to OX to intersect OY at C. Then,
C → (0, 10)
∴ Work done when the distance travelled by the body is 2 units = 10 units.
(ii) Clearly y = 0 when x = 0. So, the work done when the distance travelled by the body is 0 units is 0 units.