Answer:
Explanation:
From the second law of Newton movement laws, we have:
, and we know that a is the acceleration, which definition is:
, so:
The next step is separate variables and integrate (the limits are at this way because at t=0 the block was at rest (v=0):
(This is the indefinite integral), the definite one is:
The sample appears to have gone through 3 half-lives
1st half life: 1000 to 500 g
2nd half life: 500 to 250 g
3rd half life: 250 to 125 g
The duration of a half-life, therefore, can be inferred to be 66 ÷ (3) = 22 days.
After a 4th half life, there will be 125÷2= 62.5 g.
At this point, an additional 22 days will have passed, for a total of 88 days.
Answer is C.
Answer:
B. 30 m down
Explanation:
In physics we have two types of quantities:
- Scalar quantity: it is a quantity which only has a magnitude (e.g: mass and time are scalar quantities, since they only have a magnitude)
- Vector quantity: it is a quantity which has both a magnitude and a direction (e.g: velocity is a vector quantity, since it has a magnitude (the speed) and a direction)
In this problem, we have:
A. 100 ounces of water --> scalar (this is a volume, which has only a magnitude)
B. 30 m down --> vector (this is a displacement, which has both a magnitude (30 m) and a direction (down)
C. 88 mi/s --> scalar (this is a speed, which has only a magnitude)
D. 45 gallons in a bucket --> scalar (this is a volume, which has only a magnitude)
So, the correct option is B.
Answer:
the distance travelled from the bullet to the target is 391m
Explanation:
Hello! To solve this exercise we must follow the following steps.
1. the bullet travels with constant speed which means that the distance traveled to the target is given by the following equation
X=(V1)(T1)
where
X=target distance
V1=bullet speed=460m/s
T1=
time it takes for the bullet to reach the target
2. The distance the sound travels is given by the following equation (it is the same as the distance from the person to the target)
X=(V2)(T2)
X=
target distance
V2= speed of sound=340m/s
T2= time it takes the sound of the Bullet to return.
3. The total time it takes for the person to hear the bullet(T=2s) is the sum of the time it takes for the bullet to reach the target, plus the time it takes for the sound to reach the person, with the above we infer the following equation
T=T1+T2
2=T1+T2
4. Finally we use the equations found in step 1 and 2 to find the distance traveled using algebra.
the distance travelled from the bullet to the target is 391m
Answer: at the same time
Explanation: in a vacuum, there isnt air, right? so there isnt gravity pushing down on the heavier object, so they will both land at the same time.
good? :)
