Answer:
1. 18.25 m/s
2. 0 m/s
Explanation:
1.So the centripetal acceleration of the ball at this lowest point must be, taking gravity into account

The speed at this point would then be


2. Similarly, if T = mg, then the centripetal acceleration must be

As the ball has no centripetal acceleration, its speed must also be 0 as well.
Answer:
B. Dust storm
Explanation:
A meteorologist would predict dust storm most likely. Before dust storm the air condition and air pressure reduces in the particular area which indicate towards a dust storm. As pressure of a region reduces the air of the neighboring area try to maintain that pressure and rush towards low pressure area and causes dust storm.
I think that when work is done and a force istransferred an object must move in the direction of the force.
The north celestial pole (and also the south) are described as two imaginary points that project on the axis of rotation of the earth, indefinitely towards space and that intersects with the celestial sphere (Remember that the earth has a slight inclination with respect to to its axis of rotation). The north and south celestial poles are directly above the head of someone located at the north or south pole of the earth.
Correct Answer is A.
So we want to know what is the distance d of the object from the lens if the height of the object is h=6 cm, focal length of the lens is f=5 cm and the distance d=15 cm is the distance of the object from the lens. From the formula for the convex lens 1/f=(1/D + 1/d) where D is the distance of the image from the lens we can get D after solving for D: 1/D=(1/f) - (1/d),
1/D=(1/5)-(1/15)=0.2-0,06667=0.13333 so f=1/0.13333=7.500187 cm. Rounded to the nearest hundredth D=7.50 cm. That is very close to 7.69 cm so the correct answer is the third one.