Answer:

Explanation:
We are given that Initial speed of block=

We have to find the approximate acceleration of the block at the instant that it reaches highest point on the inclined plane.
By Newton's second law

We know that 


g=
Substitute the values then we get



Hence, the approximate acceleration of the block=
Where negative sign indicates that the block is moving in downward direction.
Answer:
Frequency = 3.19 * 10^14 Hz or 1/s
Explanation:
Relationship b/w frequency and wavelength can be expressed as:
C = wavelength * frequency, where c is speed of light in vacuum which is 3.0*10^8 m/s.
Now simply input value (but before that convert wavelength into meters to match the units, you do this by multiply it by 10^-9 so it will be 940*10^-9)
3.0 * 10^8 = Frequency * 940 x 10^-9
Frequency = 3.19 * 10^14 Hz or 1/s
Answer:
b. The balloons will decrease to half their original size.
Explanation:
When driving on roads that may be slippery, do not make any sudden changes in speed or direction. Option D is correct.
<h3 /><h3>What is a slippery surface?</h3>
The slick road sign serves as a warning. When the road is wet or ice, drivers should use extra caution and reduce their speed. When the weather is bad, avoid making any rapid changes in direction.
When driving on roads that may be slippery, do not make any sudden changes in speed or direction. It may cause accident because the vehicle can lose their balance.
Hence, option D is correct.
To learn more about the slippery surface, refer to the link;
brainly.com/question/1953680
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