Differential Equations - Online Test

Q1. Find the particular solution of the differential equation , given that y = 0 and x = 0.
Answer : Option D
Explaination / Solution:



Q2. In a bank, principal increases continuously at the rate of r% per year. Find the value of r if Rs 100 double itself in 10 years (loge2 = 0.6931).
Answer : Option B
Explaination / Solution:

Let P be the principal at any time t. then,


When P = 100 and t = 0., then, c = 100, therefore, we have:

Now, let t = T, when P = 100., then;



Q3. In a bank, principal increases continuously at the rate of 5% per year. An amount of Rs1000 is deposited with this bank, how much will it worth after 10 years 
Answer : Option D
Explaination / Solution:

Here P is the principal at time t

When P = 1000 and t = 0 ., then ,
c = 1000, therefore, we have :



Q4. Solution of is
Answer : Option C
Explaination / Solution:



Q5. General solution of is
Answer : Option B
Explaination / Solution:



Q6. To form a differential equation from a given function
Answer : Option A
Explaination / Solution:

We shall differentiate the function equal to the number of arbitrary constant so that we get equations equal to arbitrary constant and then eliminate them to form a differential equation

Q7. Forming a differential equation representing the given family of curves by eliminating arbitrary constants a and b fromyields the differential equation
Answer : Option B
Explaination / Solution:



Q8.

Forming a differential equation representing the given family of curves by eliminating arbitrary constants a and b from  yields the differential equation


Answer : Option A
Explaination / Solution:

2yy=2xyy=xyy′′+y2+1=0
Q9. Forming a differential equation representing the given family of curves by eliminating arbitrary constants a and b from yields the differential equation
Answer : Option A
Explaination / Solution:



Q10.

Forming a differential equation representing the given family of curves by eliminating arbitrary constants a and b from  yields the differential equation


Answer : Option C
Explaination / Solution: