Physics - Online Test
Q1. The word Science originates from the Latin verb Scientia meaning
Answer : Option B
Explaination / Solution:
The phrase "scientia potentia est" (or "scientia est potentia" or also "scientia potestas est") is a Latin aphorism meaning "knowledge is power"
Q2. The scalar product of two vectors A and B in terms of the magnitudes and angle is
Answer : Option A
Explaination / Solution:
The scalar product of two vectors can be constructed by taking the component of one vector in the direction of the other and multiplying it times the magnitude of the other vector. This can be expressed in the form
Q3. The three elements of a generalized communication system are
Answer : Option A
Explaination / Solution:
In communication the Transmitter helps in transmitting the signal through communication channel which acts as a physical path that connects transmitter to a receiver.And the receiver receives the transmitted signal and converts those signals in their original form.
Q4. Vectors can be added by
Answer : Option A
Explaination / Solution:
The sum of two or more vectors is called the resultant. The resultant of two vectors can be found using either the triangle method or the parallelogram method.
Q5. Thermodynamics is the branch of physics that deals with.
Answer : Option B
Explaination / Solution:
Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work. It deals with the relations between heat and other forms of energy (such as mechanical, electrical, or chemical energy), and, by extension, of the relationships between all forms of energy.
Q6. If electrons move out of a body to another body every second, how much time is approximately required to get a total charge of 1 C on the other body?
Answer : Option A
Explaination / Solution:
We know that 1 Coulomb = 6.242×1018 eletrons
given 109 electrons take 1 secs
=> 109 electrons ------> 1 sec
=> 1 electrons ---------> secs
=> 6.242×1018 ------>
= 6.242×109 secs = years
=197.93 years= 200 years approx
Q7. Elasticity is the property of a body, by virtue of which
Answer : Option C
Explaination / Solution:
When external force is applied on the solid bodies, the solid bodies get deformed. The atoms or molecules are displaced from their equilibrium positions causing a change in the interatomic ( or intermolicular ) distances. When the deforming foce is removed, the interatomic forces tend to drive them back to their original postions. Thus the body regains its original shape and size.
Q8. Each element is associated with
Answer : Option D
Explaination / Solution:
No Explaination.
Q9. According to first law of motion
Answer : Option C
Explaination / Solution:
If net force act on a body then acceleration of the body will also be zero.Hence velocity will not be changed i.e. it continues in its existing state of rest or uniform motion in a straight line.
Q10. The main reason for preferring usage of AC voltage over DC voltage
Answer : Option D
Explaination / Solution:
By using the phenomenon of mutual induction, transformers allow us to easily change voltage of AC. This is necessary to cut down poer losses while supplying electricity to our homes
