Q. A snack contains 200 calories, with 10 grams of protein, 20 grams of carbohydrates, and 5 grams of fat. What percentage of the total calories comes from protein? (2019)
A.
10%
B.
20%
C.
25%
D.
30%
Solution
Calories from protein = 10g * 4 = 40 calories. Percentage = (40/200) * 100 = 20%.
Q. A solenoid has a length of 1 m and a cross-sectional area of 0.01 m². If the magnetic field inside the solenoid is 0.2 T, what is the magnetic flux through one turn of the solenoid?
A.
0.002 Wb
B.
0.01 Wb
C.
0.02 Wb
D.
0.1 Wb
Solution
Magnetic flux (Φ) = B * A = 0.2 T * 0.01 m² = 0.002 Wb. For one turn, the flux is 0.002 Wb.
Q. A solenoid produces a magnetic field similar to that of a bar magnet. What is the primary factor that determines the strength of the magnetic field in a solenoid? (2021)
A.
Length of the solenoid
B.
Number of turns per unit length
C.
Material of the solenoid
D.
Current flowing through the solenoid
Solution
The strength of the magnetic field in a solenoid is primarily determined by the number of turns per unit length and the current flowing through it.
Correct Answer:
B
— Number of turns per unit length
Q. A solenoid produces a magnetic field similar to that of a bar magnet. What is the main factor that affects the strength of the magnetic field in a solenoid? (2021)
A.
Length of the solenoid
B.
Number of turns per unit length
C.
Material of the solenoid
D.
Current flowing through the solenoid
Solution
The strength of the magnetic field in a solenoid is primarily affected by the number of turns per unit length and the current flowing through it.
Correct Answer:
B
— Number of turns per unit length
Q. A solenoid produces a uniform magnetic field inside it. What factors affect the strength of this magnetic field?
A.
Length of the solenoid
B.
Number of turns per unit length
C.
Current through the solenoid
D.
All of the above
Solution
The strength of the magnetic field inside a solenoid is affected by the number of turns per unit length and the current flowing through it, as well as the length of the solenoid.
Q. A solenoid with a length of 1 m and a cross-sectional area of 0.01 m² carries a current of 5 A. If the magnetic field inside the solenoid is uniform, what is the magnetic field strength?
A.
0.1 T
B.
0.2 T
C.
0.5 T
D.
1 T
Solution
The magnetic field inside a solenoid is given by B = μ₀ * (N/L) * I. Assuming N/L = 1 for simplicity, B = μ₀ * I = 4π × 10^-7 T*m/A * 5 A = 0.5 T.
Q. A solid cone rolls down an incline. If its height is h, what is the relationship between its potential energy and kinetic energy at the bottom?
A.
PE = KE
B.
PE = 2KE
C.
PE = 3KE
D.
PE = 4KE
Solution
For a solid cone rolling down an incline, the potential energy at height h is converted into translational and rotational kinetic energy, leading to PE = 2KE.
Q. A solid cylinder and a hollow cylinder of the same mass and radius are released from rest at the same height. Which one will have a greater speed at the bottom?
A.
Solid cylinder
B.
Hollow cylinder
C.
Both have the same speed
D.
Depends on the mass
Solution
The solid cylinder has a smaller moment of inertia compared to the hollow cylinder, thus it will have a greater speed at the bottom.
