Answer:
72 m
Explanation:
Given:
v₀ = 0 m/s
v = 60 m/s
a = 25 m/s²
Find: Δx
v² = v₀² + 2aΔx
(60 m/s)² = (0 m/s)² + 2 (25 m/s²) Δx
Δx = 72 m
Answer:
The density of the block is 7.4g/ml.
Explanation:
We can determine the volume of the metal block by taking the difference between the volumes measured in the graduated cylinder:

Now, as we know that the average density of an object is calculated dividing its mass by its volume, we can calculate the density ρ of the metal block using the expression:

Finally, it means that the density of the metal block is 7.4g/ml.
Answer:
24.3 degrees
Explanation:
A car traveling in circular motion at linear speed v = 12.8 m/s around a circle of radius r = 37 m is subjected to a centripetal acceleration:

Let α be the banked angle, as α > 0, the outward centripetal acceleration vector is split into 2 components, 1 parallel and the other perpendicular to the road. The one that is parallel has a magnitude of 4.43cosα and is the one that would make the car slip.
Similarly, gravitational acceleration g is split into 2 component, one parallel and the other perpendicular to the road surface. The one that is parallel has a magnitude of gsinα and is the one that keeps the car from slipping outward.
So 



The electron is accelerated through a potential difference of

, so the kinetic energy gained by the electron is equal to its variation of electrical potential energy:

where
m is the electron mass
v is the final speed of the electron
e is the electron charge

is the potential difference
Re-arranging this equation, we can find the speed of the electron before entering the magnetic field:

Now the electron enters the magnetic field. The Lorentz force provides the centripetal force that keeps the electron in circular orbit:

where B is the intensity of the magnetic field and r is the orbital radius. Since the radius is r=25 cm=0.25 m, we can re-arrange this equation to find B:
Answer:
I think the answer might be the 2nd one or 3rd one.