# When a certain rubber band is stretched a distance of x, it exerts a restoring force of magnitude

1. F = ax + bx2
2. Where a and b are constants. The work done in stretching this rubber band from x = 0 to x = L is
1. aL2 + bLx3
2. aL + 2bL2
3. a + 2bL
4. bL
5. aL2/2 + bL3/3

# Find the curl of a given vector at the point (1, 2, 3)

1. $\dpi{80}&space;\fn_jvn&space;V&space;=&space;(2x&space;-&space;y^{2})\hat{i}&space;+&space;(3z&space;+&space;x^{2})\hat{j}&space;+&space;(4y&space;-&space;z^{2})\hat{k}$
1. i + 6k
2. 6K
3. 0
4. i
5. i – 6k

1. 13.6 eV
2. 27.4 eV
3. 54.4 eV
4. 108.8 eV
5. 122.4 eV

# When a hydrogen atom is raised from the ground state to an excited state:

1. Both K.E and P.E increase
2. Both K.E and P.E decrease
3. P.E increases, K.E decreases
4. K.E increases, P.E decreases

# The galaxy in which we live is:

1. milky way
3. spiral galaxy
4. irregular galaxy

1. 10-6 seconds
2. 10-8 seconds
3. 10-10 seconds
4. 10-12 seconds

# The energy which is released when an atom is formed from its constituent particles?

1. Atomic energy
2. Binding energy
3. Nuclear energy
4. Thermal energy

# In 1911, Rutherford concluded that the central part of the atom called the nucleus is:

1. Positively charged
2. Negatively charged
3. Both positively and negatively charged
4. Electrically neutral

# A force F = (5, 3, -6) is applied at a point r = (1, 0, -3) m. Calculate the torque due to this force:

1. 7i – 9j + 3k
2. -9i + 2j + 3k
3. 9i – 9j + 3k
4. 3i – 3j – k