[Solved] JEXPO 2018 Physics Question Paper
[Solved] JEXPO 2018 Physics Question Paper
JEXPO 2018 Chemistry Question Paper with Solution
Q.1) What is the angle between incident and reflected rays when a ray of light is incident normally on a plane mirror?
90°
Answer
Correct Answer:
Explanation
When ray of light incident normally on a plane mirror, then incident angle = 0°.
∴ Reflection angle also be 0° [according to the 2nd law of reflection of light].
Again, we know that in that case direction of incident ray and reflected ray are opposite to each other.
Hence, the required angle must be 180°.
Q.2) Which mirror has a wider field of view?
Answer
Correct Answer:
Explanation
Convex mirror because a mirror is diverging in nature. Light rays incident at its extreme corners gets diverged following laws of reflection. Hence if we draw the diagram we can clearly understand that the reflected rays follow a wider path. While in case of a plane mirror the divergence is not so large.
Q.3) An object of size 2.0 cm is placed perpendicular to the principal axis of a concave mirror. The distance of the object from the mirror equals the radius of curvature. The size of the image will be
Answer
Correct Answer:
Explanation
Size of the image must be same as the object size if an object is placed perpendicular to the principal axis of a concave mirror at a distance equal to 2f or r (radius of curvature).
Q.4) On a rainy day, small oily films on water show brilliant colours. This is due to
Answer
Correct Answer:
Explanation
No explanation
Q.5) Variation of resistance of semiconductor with temperature is represented by which graph?
Answer
Explanation
For semiconductor, resistance decreases with increases the temperature.
Q.6) How much work is done in moving 4C across two points having potential difference 10V?
Answer
Correct Answer:
Explanation
Work-done in moving a electrical charge, W = Potential difference (V) × amount of charge (Q) ⇒ 10 × 4 Joules = 40 J
Q.7) Rectifier is used to convert
Answer
Correct Answer:
Explanation
No explanation.
JEXPO 2018 Chemistry Question Paper with Solution
Q.8) If a 24V and a 10V battery series opposing, total voltage is
Answer
Correct Answer:
Explanation
According to the question, both the batteries are connected in opposite direction.
Thus, total voltage = (24 − 10) V ⇒ 14 V
Q.9) What is the equivalent resistance between A and B?
Answer
Correct Answer:
Explanation
4Ω and 2Ω are connected in series [see figure].
∴ Equivalent resistance of 4Ω and 2Ω resistances = (4 + 2)Ω ⇒ 6Ω.
Again 6Ω and 3Ω resistances are connected in parallel combination.
Thus, the required equivalent resistance between A and B =
6×36+3=2 Ω
Q.10) A car runs on a circular track at a constant speed. The circular track has a radius of 100 m. If the car takes 62.8 seconds on each lap, it’s average speed is
Answer
Correct Answer:
Explanation
By the definition of average speed, we have
Average speed =
total distance total time⇒
circumference of circular track total time⇒
2×3.14×100 62.8ms−1 = 10 ms−1
Q.11) Two persons start running towards each other from two points that are 120 m apart. First person runs with a speed of 5 m/s and the other with a speed of 7 m/s. Both the persons meet after
Answer
Correct Answer: