The answer is B tell me if I am wrong.
Answer:
<em>Answer: positive velocity & negative acceleration</em>
Explanation:
<u>Accelerated Motion</u>
Both the velocity and acceleration are vectors because they have magnitude and direction. When the motion is restricted to one dimension, i.e. left-right or up-down, the direction is marked with the sign according to some preset reference.
The locomotive is moving at a certain speed with a (so far) unknown sign but the acceleration has a negative sign. Since the locomotive comes to a complete stop it means the velocity and the acceleration are of opposite signs.
Thus the velocity is positive.
Answer: positive velocity & negative acceleration
<span>The answer is C. temperature, light level, species of bacteria. All three variables are considerations regarding the reproduction rate of the bacteria. The other three answer choices can be eliminated easily because they each contain at least one irrelevant variable. In particular, all three contain a variable that makes reference to Jack's personal characteristics. These do not have any impact on the experiment and readily stand out to disqualify the entire answer choice.</span>
Answer:
1.06 secs
Explanation:
Initial speed of sled, u = 8.4 m/s
Final speed of sled, v = 5.8 m/s
Coefficient of kinetic friction, μ = 0.25
Using the impulse momentum theory, we know that the impulse applied to the sled is equal to change in momentum of the sled:
FΔt = mv - mu
where m = mass of the object
Δt = time interval
F = force applied
The force applied on the sled is the frictional force, which is given as:
F = -μmg
where g = acceleration due to gravity
Therefore:
-μmgΔt = mv - mu
-μmgΔt = m(v - u)
-μgΔt = v - u
Making Δt subject of formula:
Δt = (v - u) / -μg
Δt = (5.8 - 8.4) / (-0.25 * 9.8)
Δt = -2.6/ -2.45
Δt = 1.06 secs
It took the sled 1.06 secs to travel from A to B.
Answer:
the distance between adjacent fringes is increased by a factor o 2
Explanation:
To find how the distance between fringes is modified you can use the following formula for the calculation of the distance between fringes:

D: distance to the screen
d: distance between slits
λ: wavelength of the light
if d is decreased by a factor of 2, that is d'=1/2d, you have:

hence, the distance between adjacent fringes is increased by a factor o 2