Answer: the golf ball with smooth surface would hit the ground first.
Jusitification:
An analysis of forces show two vertical forces acting on the golf balls.
1) one force is the weight (mg) which is vertical downward
2) the other force is the drag force exerted by the air on the golf balls, and it is vertical upward.
3) the drag force opposes the weight, so the acceleration downward is determined by the difference of the weiight and the drag force, until the balls reach the terminal speed (when the drag force equals the weight).
4) the drag force depends on the shape and area of the object falling. Being the surface of one ball smooth implies that the drag force will be less than the one on the other ball.
5) less drag force implies that the terminal velocity of the smooth ball will he higher, ant then it will hit the ground first.
Well first of all, here's something you're going to need:
Power = (energy) / (time) 1 watt = (1 joule) per second
Energy = (power) x (time) 1 joule = (1 watt) x (1 second)
At this point, your progress grinds to a stop, because, technically, the
current alone doesn't tell you the power. In other words, 'Amperes'
alone doesn't give you the 'watts'.
Power (watts) = (amperes) times (volts) .
So you need to either go ask somebody or else <em>assume</em> the <u>voltage</u>
of the outlet that the microwave oven is plugged into. Without it,
the question can't be answered.
I'm going to assume that you live and go to school somewhere in the USA,
Canada, or Mexico. If that's true, then the outlets in your house supply
electrical energy at 120 volts, and everything you plug into them is designed
to run on 120 volts. Now you have enough information to solve the problem.
Power = (15 amperes) x (120 volts) = 1,800 watts
Energy = (power) x (time) =
(1,800 watts) x (20 minutes) x (60 seconds/minute) =
2,160,000 watt-seconds = <em>2,160,000 joules</em>
Answer:
The scattering angle is 0.80
Explanation:
As we know
Wave length = h/mc (1-cos α) --1
W = mc^2
m = E/c^2
Substituting this in equation 1 we get
Wavelength = hc/E (1-cos α)
Substituting the given values, we get -
0.95*10^-9 = [(6.626 *10^-34 * 2.998 *10^8)/5.111*1000*1.6*10^-19} (1-cos α)
(1-cos α) = 1.14 *10^-10
cos α = 1- 1.14 *10^-10
α = 0.80
Answer:
period of rotation is 9.9843 years
Explanation:
Given data
sides = 1.0×10^12 m
to find out
period of rotation
solution
first we use the gravititional formula i.e
F(g) = 2 F cos 30
here F = G × mass(sun)² / radius²
F = 6.67 × 
× (1.99× 
)² / (1× )²
so
F(g) = 2 × 6.67 × × (1.99× )² / (1× )² × (1.73/2)
F(g) = 4.57 × 
N
and
by the law of sines
r/sin30 = s/sin120
so r will be
r = 1.0×10^12 (0.5/.87)
r = 5.75 × 
m
we know that gravititional force = centripetal force
so here
centripetal force = mv² /r
centripetal force = 1.99× v² / 5.75 ×
so
4.57 × = mv² /r
4.57 × = 1.99× v² / 5.75 ×
v² = 4.57 × × 5.75 × ![10^{11} / 1.99× [tex]10^{30}](https://tex.z-dn.net/?f=10%5E%7B11%7D%20%2F%201.99%C3%97%20%5Btex%5D10%5E%7B30%7D)
and
v = 11480 m/sec
and we know period of rotation formula
t = d /v
t = 2 
r /v
t = 2 × × 5.75 × [tex]10^{11} / 11480
t = 314 × [tex]10^{5} / 31536000 year
t = 9.9843 year
so period of rotation is 9.9843 years
Answer:
A. twice as fast.
Explanation:
m = Mass of skater
h = Height from where the skater starts
g = Acceleration due to gravity = 9.81 m/s²
Here the kinetic and potential energies balance each other
Velocity from 7 m
Velocity from 4 m
Dividing the two equations
So, the velocity of the skater is twice as fast
