Answer:
a)mass = 300kg
b) no of atoms = 1.81 x 10^26atoms.
c)Fission Activity = 207Bq
d) no of fissions = 1.79 × 107 d^-1
Explanation:
a)mass= (3×10-4)(10^6kg) = 300kg
b) no of atoms = (300kg) X (6.022×10^23/kg) = 1.81 x 10^26atoms.
c)Fission Activity = (0.69)(300kg) = 207Bq
d) no of fissions = (207)(86400) = 1.79 × 107 d^-1
Answers:
1) A process that occurs when an object or a particle moves, referred to as kinetic energy
2) A potential energy is a stored amount of energy that changes depending on the relative positions.
3) Potential Energy is the energy stored in an object due to its position. Kinetic Energy is the energy of motion in a moving object.
4)
a) C and B
b) A
c) From B to A or from C to A
d) From A to B or from A to C
Answer:
C
Explanation:
I did the math and got c so
Answer:
115 m/s, 414 km/hr
Explanation:
There are two forces acting on a skydiver: gravity and air resistance (drag). At terminal velocity, the two forces are equal and opposite.
∑F = ma
D − mg = 0
D = mg
Drag force is defined as:
D = ½ ρ v² C A
where ρ is the fluid density,
v is the velocity,
C is the drag coefficient,
and A is the cross sectional surface area.
Substituting and solving for v:
½ ρ v² C A = mg
v² = 2mg / (ρCA)
v = √(2mg / (ρCA))
We're given values for m and A, and we know the value of g. We need to look up ρ and C.
Density of air depends on pressure and temperature (which vary with elevation), but we can estimate ρ ≈ 1.21 kg/m³.
For a skydiver falling headfirst, C ≈ 0.7.
Substituting all values:
v = √(2 × 80.0 kg × 9.8 m/s² / (1.21 kg/m³ × 0.7 × 0.140 m²))
v = 115 m/s
v = 115 m/s × (1 km / 1000 m) × (3600 s / hr)
v = 414 km/hr
