A fullerene is an allotrope of carbon in the form of a hollow sphere, ellipsoid, tube, and many other shapes. Spherical fullerenes, also referred to as Buckminsterfullerenes or buckyballs, resemble the balls used in association football. Cylindrical fullerenes are also called carbon nanotubes (buckytubes).
Answer:
4 km/hr
Explanation:
suppose 's' is Diane's speed with no current.
't' represents time in hrs.
Using the formula:
Distance = speed 's' x time 't'
-> when she swims against the current, equation will be,
5= (s-2)t
t= 5/(s-2)
->when she was swimming with the current, equation is,
15= (s+2) t
t= 15/(s+2)
equating eq(1) and (2)
5/(s-2) = 15/(s+2)
5s + 10 = 15s - 30
40= 10s
s= 40/10
s=4
Therefore, if there were no current, her speed is 4km/hr
Answer:


where
Pa = Gravitational potential energy of satellite A
Pb = Gravitational potential energy of satellite B
G = gravitational constant
Me = Mass of the earth
Ma = Mass of satellite A
Mb = Mass of satellite B
Re = Radius of the earth
Pb/Pa = (-GMeMb/Re) / (-GMeMa/Re)
Pb/Pa = Mb/Ma
Explanation:
Answer:
792 J
Explanation:
The total energy of the ball is E = U + K where U = potential energy = mgh and K = kinetic energy = 1/2mv²
E = mgh + 1/2mv² where m = mass of ball = 2.0 kg, g = acceleration due to gravity = 9.8 m/s², h = height of building = 20.0 m, v = initial velocity of ball = 20.0 m/s.
So, substituting the values of the variables into E, we have
E = mgh + 1/2mv²
= 2.00 kg × 9.8 m/s² × 20.0 m + 1/2 × 2.00 kg × (20.0 m/s)²
= 392 J + 400 J
= 792 J
Answer:
b) lattice energy
Explanation:
A solution is said to have colligative property when the property depends on the solute present in the solution.
Colligative property depend upon on the solute particle or the ion concentration not on the identity of solute.
osmotic pressure, vapor pressure lowering , boiling point elevation and freezing point lowering all depend upon solute concentration so they will not have colligative property so, the answer remains option 'b' which is lattice energy.