E. all of the above
An umbrella tends to move upward on a windy day because _<span>A. buoyancy increases with increasing wind speed </span>
<span>B. air gets trapped under the umbrella and pushes it up </span>
<span>C. the wind pushes it up </span>
<span>D. a low-pressure area is created on top of the umbrella </span>
Answer:
The magnitude of the tension in he string is equal to the magnitude of the weight of the object.
Explanation:
According to the Newton's 1st law, An object will remain at rest or in uniform motion in a straight line unless acted upon by an unbalanced force.
In here, the elevator is moving with a constant speed. So the object must have the equal constant speed. Which means, it has a uniform motion. According to Newton's 1st law, the total unbalanced force on the object must be zero . As we know, there are only two forces are on the object and they are,
The tension in string(T) , The weight of the object(W) .
∴ F = 0
T - W = 0
So to balanced those forces, the magnitude of the tension in the string must be equal to the magnitude of the weight of the object.
Explanation:
The new volume of water = 25 ml
The old volume of water = 15 ml
The difference = 25 - 15 but what are the units?
Since the question asks for force, the units must start out as 10 mL
In water 1 mL has a mass of 1 gram, so the answer is 10 grams.
Grams are units of mass, not weight. You should convert this into newtons.
10 grams = 1/1000 = 0.01 kg
1 kg has a weight of 9.81 Newtons
0.01 kg has a weight 0.081 Newtons
If you have never seen a Newton before, then the answer is 10 grams
Answer:
Frequency, f = 0.2 Hz
Explanation:
We have,
A baseball player throws 4 balls every 20 seconds.
It is required to find the frequency of the baseball.
Frequency of an object is defined as the number of times an event occurs. It is given by number of throws per unit time. It can be given by :

So, the frequency of his throw is 0.2 Hz.