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3 years ago

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A sample of fluorine-18 in a laboratory has an initial mass of 50mg.flourine-18 has a half life of 1.8 hours Calculate the amoun

t of time it will take for the initial mass of fluorine-18 to be reduced from 59 mg to 12.5mg

1 answer:

Mekhanik [1.2K]3 years ago

7 0

It will take 3.6 hours to get reduced from 50 to 12.5 g..

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In thermodynamics, work is typically done by

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The answer is gases

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2 years ago

You and a friend each hold a lump of wet clay. Each lump has a mass of 30 grams. You each toss your lump of clay into the air, w

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Answer:

$\ \text{m/s}$

Explanation:

$u_1$ = Velocity of one lump = $3x+3y-3z$

$u_2$ = Velocity of the other lump = $-4x+0y-4z$

m = Mass of each lump = $30\ \text{g}$

The collision is perfectly inelastic as the lumps stick to each other so we have the relation

$mu_1+mu_2=(m+m)v\\\Rightarrow m(u_1+u_2)=2mv\\\Rightarrow v=\dfrac{u_1+u_2}{2}\\\Rightarrow v=\dfrac{3x+3y-3z-4x+0y-4z}{2}\\\Rightarrow v=-0.5x+1.5y-3.5z=\ \text{m/s}$

The velocity of the stuck-together lump just after the collision is $\ \text{m/s}$ .

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2 years ago

Two objects, A and B, each of mass o.22 kg, are moving at 0.34 m/s directly toward each other. What is the speed of Object A aft

ki77a [65]

Theoretically, if the objects have the same mass and are moving towards each other at a speed of $0.34m s^{-1}$ , after a perfectly elastic collision, the object A is supposed to move with the same velocity in the opposite direction.

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2 years ago

An airplane is being pushed West by its engines with a force of 350 N as it starts to take off the runway at the Atlanta airport

Marizza181 [45]

Answer:

option C

Explanation:

given,

Force by the engine on plane in West direction = 350 N

Frictional force on the runway = 100 N in east

force exerted by the wind = 100 N in east

net force and direction = ?

consider west to be positive and east be negative.

when airplane will be moving there will be frictional as well as wind resistance will be acting in opposite direction of airplane

Net force = 350 N - 100 N - 100 N

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2 years ago

If five joules were required to move a crate in 3.7 seconds, what power was applied?

AleksAgata [21]

Answer:

The answer to your question is 1.35 Watts

Explanation:

Data

Work = W = 5 J

time = t = 3.7 s

Power = P = ?

Formula

Power is a rate in which work is done or energy is transferred over time

P = $\frac{W}{t}$

Substitution

$P = \frac{5}{3.7}$

Result

P = 1.35 W

8 0

3 years ago