Answer:
60 km
Explanation:
For an object (or a person, such as in this case) moving at constant speed, the speed is equal to the ratio between the distance travelled and the time taken:
where
v is the speed
d is the distance
t is the time taken
In this case, we have:
v = 120 km/h is the speed
t = 30 min = 0.5 h is the time taken
Therefore, we can rearrange the equation to find the total distance travelled:
Answer:
0.075A
Explanation:
We can consider this system as a circuit, hence we can take the current from the formula for the electric power as follow
I hope this is useful for you
regards
To solve this problem it is necessary to use the conservation equations of both kinetic, rotational and potential energy.
By definition we know that
Where,
KE =Kinetic Energy
KR = Rotational Kinetic Energy
PE = Potential Energy
In this way
Where,
m = mass
v= Velocity
I = Moment of Inertia
Angular velocity
g = Gravity
h = Height
We know as well that 
for velocity (v) and Radius (r)
Therefore replacing we have
![[tex]h= \frac{1}{2} \frac{v^2}{g} +\frac{1}{2} \frac{I}{mg}(\frac{v}{r})^2](https://tex.z-dn.net/?f=%5Btex%5Dh%3D%20%5Cfrac%7B1%7D%7B2%7D%20%5Cfrac%7Bv%5E2%7D%7Bg%7D%20%2B%5Cfrac%7B1%7D%7B2%7D%20%5Cfrac%7BI%7D%7Bmg%7D%28%5Cfrac%7Bv%7D%7Br%7D%29%5E2)
[/tex]
Therefore the height must be 0.3915 for the yo-yo fall has a linear speed of 0.75m/s
In case of an object sitting at rest on another base, there are two equal and opposite forces – Normal force and the gravity.
Answer: Option A
<u>Explanation:
</u>
When an object is placed at rest position on another object, there is a force exerted by the surfaces of the two contact objects. This force is denoted as Normal Force.
When an object such as a box is placed on a shelf, its surface exerts a contact force on the base of the shelf- The Normal force directed upward. Meanwhile, the gravity stays at its action and tries to pull the box towards itself.
Both of these forces however are equal and opposite and therefore, there is zero net force on the box. That's why it remains at rest, holding on Newton's third law.
