Question

1. which of the following is not true about magnetic field lines
a) mag. field lines flow from North to South inside the magnet
b) mag. field lines do not cross
c) mag. field line density is proportional to field strength
d) mag. field is strongest closest to the ends of a bar magnet

is the answer c?

2. Both the electric and gravitational fields:
a) involve mass
b) decrease linearly with distance
c) decrease exponentially with distance
d) contain the same constant

would the answer be d?

Answer 1

1. How would they cross?

2. different constants/r^2

k Q1 Q2/r^2 versus G M1 M2/r^2

see
https://www.google.com/search?q=exponential+field+definition&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=sb#channel=sb&q=exponential+function+definition&revid=132910346&rls=org.mozilla:en-US:official

Answer 2

By the way magnetic field lines usually are draw going from N to S OUTSIDE the magnet.