17) What is the resultant vectors, when 2 vectors are at right angles to each other? (a) R= /P2+Q² (b) R=P+ Q (c) R=P-Q (d) R=/P/Q
Answers
Answered by
1
Answer:
Step 1: Initial resultant between two vectors [Ref. Fig. 1]
Resultant of
P
and
Q
,
∣
∣
∣
∣
R
∣
∣
∣
∣
2
=
∣
∣
∣
∣
P
∣
∣
∣
∣
2
+
∣
∣
∣
∣
Q
∣
∣
∣
∣
2
+2
∣
∣
∣
∣
P
∣
∣
∣
∣
∣
∣
∣
∣
Q
∣
∣
∣
∣
cosθ ....(1)
Step 2: Dot product between new resultant and
P
[Ref. Fig. 2]
When
Q
is doubled, new resultant,
R
1
=
P
+2
Q
becomes perpendicular to
P
∴
R
1
.
P
=0
⇒ (
P
+2
Q
).
P
=0
⇒ ∣
P
∣
2
+2∣
P
∣∣
Q
∣cosθ=0
⇒ cosθ=
2∣
Q
∣
−∣
P
∣
Step 3: Solving equation
Putting value of cosθ in equation (1)
∣
R
∣
2
=∣
P
∣
2
+∣
Q
∣
2
+2∣
P
∣∣
Q
∣[
2∣
Q
∣
−∣
P
∣
]
⇒ ∣
R
∣
2
=∣
Q
∣
2
⇒ ∣
R
∣=∣
Q
∣
Attachments:
Answered by
0
you will get the answer don't worry bro
Similar questions