(a) atomic number (Z)
(b) atomic mass or mass number (A)
(c) 11 electron
(l) negative, positive,0 no charge
3. Atomic number
7. mass number
1. a) 1.2v
2. b) Dalton
3. c) Atomic number
4. c) 2 volt
5. c) Ampere
6. b) 4
7. a) Mass number
8. a) 2,8
9. b) Iodine-131
10. b) k shell
6) Gold = Metal, Silver =Metal, Copper = Metal, Carbon = non-metal, Aluminum =Metal, Oxygen = non-metal, hydrogen = non-metal
I hope it's help you.
trilobites were rapidly evolving
and widespread marine organisms that
spanned a number of geologic time
periods. certain types of trilobites only
appeared in specific segments of
geologic time; therefore, when one of
these trilobites is found, you can be
certain that the rock layer it is found in
is of a certain geologic age.
as various trilobites belonged to various
periods of time, it is possible by finding out
what the type of trilobite is to also find out
when the fossil was made, that is from what
time period is the rock where it was found.
friction can some times be tricky but stick to the basics and you will be able to overcome it.
for your question i will split it in two parts
rear wheel drive and front wheel drive
basically there are two types of wheel i. e. driving and driven. so for instance if you are providing engine power to rear wheel, your rear wheels will act as driving wheels and front wheels will move because of propelling force. now suppose the car (rear wheel drive) is moving towards north then friction on rear wheels will act towards north and on front wheels it will act towards south. you can understand it like , the rear wheels are powered with engine torque so its like the ground towards south thus friction being opposing force acts towards north on wheels. you can visualize like suppose you have rotating wheel mounted over axle and you are the wheel to ground holding the axle then what will happen, wheel will stop due to friction acting in a direction such that it opposes the driving couple, so if your wheel is moving clockwise, friction will act in a direction such that moment produced is anticlockwise about polar axis(axis passing through centroid and perpendicular to plane of wheel) of wheel. now for front wheel it is the case similar to a wheel where force (here propelling force acting towards north as car is moving towards north) is applied at centre of mass, so friction will act towards south because of its opposing nature but in course of doing so it also produces moment in clockwise direction causing rotation of wheel. for front wheel drive i hope you can figure out directions based on above concept. you can also try for all wheel drive for more fun.
number of neutrons