Answer:
See explanation
Explanation:
From the formula;
0.693/t1/2 = 2.303/t log (Ao/A)
t1/2 = half life of Sodium-24
Ao = initial activity of Sodium-24
A= activity of Sodium-24 at time = t
So,
0.693/15 = 2.303/15 log (800/A)
0.0462 = 0.1535 log (800/A)
0.0462/0.1535 = log (800/A)
0.3 = log (800/A)
Antilog(0.3) = (800/A)
1.995 = (800/A)
A = 800/1.995
A = 401 Bq
ii) 0.693/15 = 2.303/30 log (800/A)
0.0462 = 0.0768 log (800/A)
0.0462/0.0768 = log (800/A)
0.6 = log (800/A)
Antilog (0.6) = (800/A)
3.98 = (800/A)
A = 800/3.98
A = 201 Bq
iii)
0.693/15 = 2.303/45 log (800/A)
0.0462 = 0.0512 log (800/A)
0.0462/0.0512 = log (800/A)
0.9 = log (800/A)
Antilog (0.9) = (800/A)
7.94 = (800/A)
A = 800/7.94
A= 100.8 Bq
iv)
0.693/15 = 2.303/60 log (800/A)
0.0462 = 0.038 log (800/A)
0.0462/0.038 = log (800/A)
1.216 = log (800/A)
Antilog(1.216) = (800/A)
16.44 = (800/A)
A = 800/16.44
A = 48.66 Bq
Answer:
Acceleration = Change in Velocity/Time
Change in Velocity = 36-18 = 18 km/h=5 m/s
Time= 5 Seconds
Acceleration = 5/5= 1 m/s2
Equation of motion,s=ut+(1/2)at2
u=18 km/h=5 m/s
t=5 s
a=1 m/s2
s= (5*5)+(1/2*1*5*5)
s=25+12.5 i.e., s=37.5 m
Hope you are clear with my explanations
Answer:
500 watts
Explanation:
Recall that the definition of power is the amount of energy delivered per unit of time.
In our case, the energy delivered is potential energy which we can estimate as the product of the weight of the object times the distance it is lifted above ground:
200 N x 10 m = 2000 Nm
then the power is the quotient of this potential energy divided the time it took to lift the object to that position:
Power = 2000 / 4 Nm/s = 500 Nm/s = 500 watts
Answer: Enceladus
Explanation:
Enceladus is a small, icy body with an undergound ocean beneath its crust. Cassini discovered that geyser-like jets spew water vapor and ice particles. It is also the sixth largest moon in Saturn and just about a tenth of the largest moon in Saturn; Titan. It is often regarded as one of the most reflective body in the solar system as a result of its icy surface.
Answer:
Scientists plan to release a space probe that will enter the atmosphere of a gaseous planet. The temperature of the gaseous planet increases linearly with the height of the atmosphere as measured from the top of a visible boundary layer, defined as 0 kilometers in altitude. The instruments on board can withstand a temperature of 601 K. At what altitude will the probe's instruments fail? A. 50 kilometers B. 80 kilometers C. 83 kilometers D. 100 kilometers E. 111 kilometers
Explanation:
A. 50 kilometers
