Answer:
d A ball is rolling down an inclined plane.
Explanation:
When path length is equal to the displacement
then we can say that the motion of the object must be in straight line so that the distance and displacement must be same
SO here we can say
a A ball on the end of a string is moving in a vertical circle.
In circular path distance and displacement is not same
b A toy train is traveling around a circular track.
In circular path distance and displacement is not same
c A train travels 5 miles east before it stops. It then travels 2 miles west.
Net displacement is 3 miles East while distance is 7 miles
d A ball is rolling down an inclined plane.
Here its motion is in straight line so we can say that path length and displacement will be same
e A ball rises and falls after being thrown straight up from the earth's surface.
In this type of to and fro motion path length is not same as displacement
Answer:
speed wind Vw = 54.04 km / h θ = 87.9º
Explanation:
We have a speed vector composition exercise
In the half hour the airplane has traveled X = 108 km to the west, but is located at coordinated 119 km west and 27 km south
Let's add the vectors in each coordinate axis
X axis (East-West)
-Xvion - Xw = -119
Xw = -Xavion + 119
Xw = 119 -108
Xwi = 1 km
Calculate the speed for time of t = 0.5 h
Vwx = Xw / t
Vwx= 1 /0.5
Vwx = - 2 km / h
Y Axis (North-South)
Y plane - Yi = -27
Y plane = 0
Yw = 27 km
Vwy = 27 /0.5
Vwy = 54 km / h
Let's use the Pythagorean theorem and trigonometry to compose the answer
Vw = √ (Vwx² + Vwy²)
Vw = R 2² + 54²
Vw = 54.04 km / h
tan θ = Vwy / Vwx
tan θ = 54/2 = 27
θ = Tan⁻¹ 1 27
θ = 87.9º
The speed direction is 87. 9th measure In the third quadrant of the X axis in the direction 90-87.9 = 2.1º west from the south
Answer:
the correct answer is C, E’= 4E
Explanation:
In this exercise you are asked to calculate the electric field at a given point
E = 
indicates that the field is E for r = 2m
E = 
(1)
the field is requested for a distance r = 1 m
E ’= k \frac{q}{r'^2}
E ’= k q / 1
from equation 1
4E = k q
we substitute
E’= 4E
so the correct answer is C
Answer:
Due to the fact that the comb is in terms of mass bigger than pieces of paper
Explanation:
In terms of mass, the comb is way too bigger than the piece of paper so it is virtually impossible for it to move towards the pieces of paper
According to Newton third law action and reaction are equal and opposite
Mathematically
P=m*v
Where
P= impulse is Newton
m=mass of the body
V= velocity of the body
Now since the comb has a greater mass it will not move to the paper, else the paper must have to move to it.
Answer:
when the object goes from the focal length to twice the focal length the image goes from infinity to twice the focal length, this image is real and inverted
Explanation:
Let's use the constructor equation to describe the image of a concave mirror
1 / f = 1 / p + 1q
where f is the focal length, p and q the distance to the object and the image, respectively
1 /q = 1/f - 1/p
tell us that the image is between the focal and twice the focal, let's calculate the position of the image
for both ends
case 1, distance to the object p = f
1 / q = 1 / f -1 / f
1 / q = 0
q = ∞
the image is in infinity
case2, distance to object p = 2f
1 / q = 1 / f - 1 / 2f
1 / q = 1 / 2f
q = 2f
the image is twice the focal length, the object and the image are at the same point
therefore the image when the object goes from the focal length to twice the focal length the image goes from infinity to twice the focal length, this image is real and inverted
