Answer: They are in the same group because they have similar chemical properties, but they are in different periods because they have very different atomic numbers.
Explanation: On Edgenuity!!
Answer:
15.71 m/s
Explanation:
We are given;
Time; t = 0.2 s
Radius; r = 0.5 m
The circumference will give us the distance covered.
Formula for circumference is 2πr
Thus; Distance = 2πr = 2 × π × 0.5 = π
Linear speed = distance/time = π/0.2 = 15.71 m/s
Answer:
On a velocity-time graph… slope is acceleration. the "y" intercept is the initial velocity. when two curves coincide, the two objects have the same velocity at that time.
Answer: There will be 75258 nuclei left at 6 pm.
Explanation:
a) half-life of the radioactive substance:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
b) Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = time for decomposition = 6 hours ( from 12 noon to 6 pm)
A = activity at time t = ?
= initial activity = 600, 000
Thus there will be 75258 nuclei left at 6 pm.
This can be calculated with the law of conservation of energy. The sky lift is starting with the speed v= 15.5 m/s and all of it's kinetic energy Ek is transformed to potential energy Ep so the energies have to be equal: Ep=Ek.
Since Ek=(1/2)*m*v² where m is mass and v is the speed, Ep=m*g*h, where m is mass, g= 9.81 m/s² and h is height. Now:
Ek=Ep
(1/2)*m*v²=m*g*h, masses cancel out,
(1/2)*v²=g*h, divide by g to get the height,
(1/2*g)*v²=h and now plug in the numbers:
h=12.245 m. Height of the hill rounded to the nearest tenth is h=12.25 m
