1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
shtirl [24]
3 years ago
8

How long will it take a sample of lead-212 (which has a half-life of 10.64 h) to decay to one-eighth its original strength?

Physics
1 answer:
Valentin [98]3 years ago
5 0

Answer:

31.92 h

Explanation:

We'll begin by calculating the number of half-lives that has elapsed. This can be obtained as follow:

Original amount (N₀) = 1

Amount remaining (N) = ⅛

Number of half-lives (n) =?

N = 1/2ⁿ × N₀

⅛ = 1/2ⁿ × 1

Cross multiply

2ⁿ = 8

Express 8 in index form with 2 as the base.

2ⁿ = 2³

n = 3

Thus, 3 half-lives has elapsed.

Finally, we shall determine the time. This can be obtained as follow:

Half-life (t½) = 10.64 h

Number of half-lives (n) = 3

Time (t) =?

n = t / t½

3 = t / 10.64

Cross multiply

t = 3 × 10.64

t = 31.92 h

Therefore, it will take 31.92 h for lead-212 to decay to one-eighth its original strength.

You might be interested in
The boom of a fire truck raises a fireman (and his equipment – total weight 280 lbf) 60 ft into the air to fight a building fire
Katen [24]

Answer:

a)Work done by fireman=   2.15  Btu

b) Time t= 0.86 sec

Explanation:

Given that

Weight = 280 lbf

We know that 1 lbf = 4.44 N

so 280 lbf = 1245.5 N

Weight =1245.5 N

Height h = 60 ft

We know that

1 ft = 0.3048 m

So 60 ft = 18.28 m

 h =18.28 m

Power = 3.5 hp

We know that

1 hp =0.74 KW

So 3.5 hp = 2.61 KW

Power = 2.61 KJ/s

So the work done by fireman = Weight x h

Now by putting the values

Work done by fireman= 1245.5 x 18.28 J

Work done by fireman=   2267.74 J

Work done by fireman=   2.26774  KJ

We know that 1 Btu= 1.05 KJ

So   2.266 KJ = 2.15 Btu

Work done by fireman=   2.15  Btu

We know that ,rate of work is called power.

Power x time =  work

2.61 x t = 2.26

So t= 0.86 sec

6 0
3 years ago
1. The speed limit on a particular freeway is 28.0 m/s (about 101 km/hour). A car
zavuch27 [327]

Answer:

the speed limit 6 seconds and the car will travel in 90m

3 0
3 years ago
Why is it that the two possible faults with inductors are short circuit and open circuit?
lukranit [14]
These are the most common type of faults not just inductors but also with other elements too like resistors,transformers, generators etc.
open circuit fault means the flow of current is disrupted some how in the circuit and the circuit stops operating. and for short circuit fault the current in the system will be pretty high and this short circuit current or fault current will always run back to the fault location, if the inductor got short circuited somehow then the fault current will only run through it because it will then provide a very low impedence path
5 0
3 years ago
What is work? how do we solve for work?​
slava [35]

Answer: Work can be calculated with the equation: Work = Force × Distance. The SI unit for work is the joule (J), or Newton • meter (N • m). One joule equals the amount of work that is done when 1 N of force moves an object over a distance of 1 m.

Explanation:

5 0
3 years ago
Read 2 more answers
Which of the following is formed by constructive erosion? 1. delta 2. gully 3. rill 4. glacier
lana [24]
1. Delta, is formed by constructive erosion.
7 0
3 years ago
Other questions:
  • When water (H2O) freezes into ice, some of the properties have changed. What stays the same?
    13·1 answer
  • Bud, a very large man of mass 130 kg, stands on a pogo stick. How much work is
    5·1 answer
  • Which of the following cannot be the result of punctuated equilibrium
    11·1 answer
  • Imagine an alternative universe where the characteristic decay time of neutrons is 3 min instead of 15 min. All other properties
    6·1 answer
  • When electric current is flowing in a metal, the electrons are movinga. at nearly the speed of light.b. at the speed of sound in
    5·1 answer
  • How many mean free paths thick must a shield be designed in order to attenuate an incident neutron beam by a factor of 1000?
    6·1 answer
  • In a collision, the __________ collision is when an unsecured driver strikes the inside of the vehicle.
    8·2 answers
  • Answer the questions below correctly (please) and I'll give brainliest!
    15·1 answer
  • How far can a bus carrying small children, travel at a rate of 60 km per hour travel in 2 1/2 hours?
    5·1 answer
  • Olivia is on a swing at the playground.
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!