Answer:
B. -2
Explanation:
The total charge on an atom is the sum of all individual charges present in it. Therefore, the total charge on this atom is given by the following formula:
where,
q = total charge on atom = ?
= no. of protons in the atom = 15
= no. of electrons in the atom = 17
= no. of neutrons in the atom = 12
= charge on proton = +1
= charge on electron = -1
= charge on neutron = 0
Therefore,
Hence the correct option is:
<u>B. -2</u>
55 J
Explanation:
Kinetic energy is given as: 0.5MV^2 where M is the mass and V is the speed of rotation. Since the masses are point masses, we calculate the point mass for each mass.
M1 = 30*0.2^2 = 1.2kgm^2
M2 = 20*0.4^2 = 3.2kgm^2
V = 5 rad/s
Calculating using the formula above, we obtain :
0.5(1.2+3.2)5^2 =0.5*4.4*25 = 55 J
All the colors of the visible spectrum
Ok so use trigonometry to work out the vertical component of velocity.
sin(25) =opp/hyp
rearrange to:
30*sin(25) which equals 12.67ms^-1
now use SUVAT to get the time of flight from the vertical component,
V=U+at
Where V is velocity, U is the initial velocity, a is acceleration due to gravity or g. and t is the time.
rearranges to t= (V+u)/a
plug in some numbers and do some maths and we get 2.583s
this is the total air time of the golf ball.
now we can use Pythagoras to get the horizontal component of velocity.
30^2-12.67^2= 739.29
sqrt739.29 = 27.19ms^-1
and finally speed = distance/time
so--- 27.19ms^-1*2.583s= 70.24m
The ball makes it to the green, and the air time is 2.58s
Option C: Later in the day, less power is developed in lifting each box
