1 Group B
Attempt any Three questions.
4x3=12
8. Derive expression for energy stored in a stretched wire.
2. Derive mirror formula - +
f
10. Use triangle law of vector addition to find magnitude and direction of
resultant of two vectors.
11. How can a body be charged positively by method of induction.
и
v
Group C
Attempt any Two numerical
4x2=8
12. Change 36 km/hr into m/s by method of dimension.
13. A wire 2m long and cross sectional area 10-6 m² is stretched 1mm by force
50N. Calculate
i) Strain
ii) Young's modulus iii) energy stored.
14. Two vectors each of magnitude 5 are inclined at 60°. Find magnitude and
direction of resultant.​

Astudent throws a water balloon with speed v0 from a height h = 1.76 m at an angle θ = 21° above the horizontal toward a target on the ground. the target is located a horizontal distance d = 9.5 m from the student’s feet. assume that the balloon moves without air resistance. use a cartesian coordinate system with the origin at the balloon's initial position. (a) what is the position vector, rtarge t, that originates from the balloon's original position and terminates at the target? put this in terms of h and d, and represent it as a vector using i and j. (b) in terms of the variables in the problem, determine the time, t, after the launch it takes the balloon to reach the target. your answer should not include h. (c) create an expression for the balloon's vertical position as a function of time, y(t), in terms of t, vo, g, and θ. (d) determine the magnitude of the balloon's initial velocity, v0, in meters per second, by eliminating t from the previous two expressions.