The needle on a compass always points in the direction of magnetic north because of the magnetic poles of earth. the compass is essentially a magnet itself, so the southern pole of the compass is attracted to the northern pole of earth.
Answer:
The force generated by a single muscle fiber can be increased by increasing the frequency of action potentials
Explanation:
The force generated by a muscle fiber is the result of the shortening of the skeletal muscle, and this force is also know as muscle tension. The larger motor units shorten along with the smaller units to produce the muscle force. The time lapsed between the beginning of the action potential in the muscle and the beginning of the contraction is the latent period. Action potential is the result of the difference electrical potential as a result of passage of an impulse along the membrane of a muscle or nerve cell.
Answer:
ratio =0.3075 T
Explanation:
The magnetic field B creates a force on a moving charge such that

Now this causes a centripetal acceleration

so
...........(i)
...............(ii)
If accelerating potential V is same and then kinetic energy equals the potential energy difference

put these value in equation (ii)
simplifying we get

for same location r will be same in both case
..............(iii)
..........(iv)
dividing (iv) and (iii) equation we get



so on solving we get
=0.3075 T
Answer:
b 2 only
Explanation:
The mass of an electron is 9.10938356 × 10⁻³¹ kilograms while the mass of a proton is 1.6726219 × 10⁻²⁷ kilograms. It can be seen that a proton is heavier than an electron.
Atoms do not always have the same number of neutrons and protons. For, example ¹³C has 6 protons and 7 neutrons.
Atoms do have most of the mass concentrated at the center called the nucleus. The nucleus has protons and neutrons. As protons have positive charge and neutrons have no charge the nucleus has a positive charge.
Answer:
The SI unit of force is the newton, symbol N. The base units relevant to force are: The metre, unit of length — symbol m. The kilogram, unit of mass — symbol kg.