Ask question

Ask question

All categories

4 years ago

6

A car starts from rest and after 7 seconds it is moving at 42 m/s. What is the car’s average acceleration? A. 0.17 m/s2 B. 1.67

m/s2 C. 6 m/s2 D. 7 m/s2 E. none of the above

2 answers:

aliya0001 [1]4 years ago

5 0

Acceleration =velocity /time
=42/7
=6

tamaranim1 [39]4 years ago

4 0

C. 6 m/s2 is correct

You might be interested in

When steam condenses 1. All of these occur. 2. None of these occur. 3. molecules move closer together. 4. it changes from the ga

True [87]

2. None of these occur

5 0

3 years ago

Read 2 more answers

In designing circular rides for amusement parks, mechanical engineers must consider how small variations in certain parameters c

Bess [88]

Answer:

Part a)

$dF = -\frac{mv^2}{r^2} dr$

Part b)

$dF = \frac{2mvdv}{r}$

Part c)

$dT = - \frac{2\pi r}{v^2} dv$

Explanation:

Part a)

As we know that force on the passenger while moving in circle is given as

$F = \frac{mv^2}{r}$

now variation in force is given as

$dF = -\frac{mv^2}{r^2} dr$

here speed is constant

Part b)

Now if the variation in force is required such that r is constant then we will have

$F = \frac{mv^2}{r}$

so we have

$dF = \frac{2mvdv}{r}$

Part c)

As we know that time period of the circular motion is given as

$T = \frac{2\pi r}{v}$

so here if radius is constant then variation in time period is given as

$dT = - \frac{2\pi r}{v^2} dv$

8 0

3 years ago

when an object is placed near a concave mirror, at what position does it forms a magnified and erect image.

alexira [117]

Answer:

Between the principal focus and the pole of the mirror

4 0

3 years ago

A machine can never be 100% efficient because some work is always lost due to .

klasskru [66]

Friction
Hope it helped

5 0

4 years ago

Read 2 more answers

Plants make food through photosynthesis, a chemical reaction. What are the starting substances of the reaction?

vekshin1

The answer is the 4th option because they don't use oxygen, that's what they produce

3 0

3 years ago

Read 2 more answers