Answer:
A. 50 m/s
Explanation:
Given in the y direction:
v₀ = 0 m/s
a = 10 m/s²
t = 4 s
Find: v
v = at + v₀
v = (10 m/s²) (4 s) + 0 m/s
v = 40 m/s
In the x direction, the velocity is constant at 30 m/s.
The overall speed is:
v² = (30 m/s)² + (40 m/s)²
v = 50 m/s
A. The molecules start packed together very tightly in a solid. Then when it turns to water, the molecules can move around each other freely, but still contained. When water turns to vapor, the molecules are going crazy moving around. They are not contained at all and bounce of of each other freely.
b. The temperature rises. (ice turns to water at 33 degrees and water turns to vapor at 212 degrees)
There are no hurricanes in Alaska because it is at the edge of the atmoshpere.
The thing that pushes the object up while it is falling is air. This force is known as "air resistance".
For a certain interval of time, an object is acted on by a constant non-zero force. For this interval of time . . . . .
A. The object is at rest. No. From F=ma, if F is not zero, the object can't remain at rest.
<em>B.</em> <em>The object's velocity changes.</em> <em>Yes.</em> From F=ma, if F is not zero, there must be acceleration.
C. The object's velocity can only increase. No. It might decrease.
D. The object is moving with constant velocity. No. From F=ma, if F is not zero, there must be acceleration.
<em>E.</em> <em>The object is accelerating.</em> <em>Yes.</em> From F=ma, if F is not zero, there must be acceleration.
