Ask question

Ask question

All categories

3 years ago

9

what is the work done by gravity when a 2.0kg ball falls to the floor from the height of 1.50m? Is it positive or negative? Expl

ain

1 answer:

Ratling [72]3 years ago

5 0

Positive because the ball is falling downwards.
Work done(Wd)= force x distance travelled in the direction of the force,
Wd=(2x9.8)x1.5

You might be interested in

A man jogs at a speed of 1.6 m/s. His dog waits 1.8 s and then takes off running at a speed of 3 m/s to catch the man. How far w

inessss [21]

Answer:

The dog catches up with the man 6.1714m later.

Explanation:

The first thing to take into account is the speed formula. It is $v=\frac{d}{t}$ , where v is speed, d is distance and t is time. From this formula, we can get the distance formula by finding d, it is $d=v\cdot t$

Now, the distance equation for the man would be:

$d_{man}=v_{man}\cdot t=1.6\cdot t$

The distance equation for the dog would be obtained by the same way with just a little detail. The dog takes off running 1.8s after the man did. So, in the equation we must subtract 1.8 from t.

$d_{dog}=v_{dog}\cdot (t-1.8)=3\cdot (t-1.8)$

For a better understanding, at t=1.8 the dog must be in d=0. Let's verify:

$d_{dog}=v_{dog}\cdot (1.8-1.8)=3\cdot (0)=0$

Now, for finding how far they have each traveled when the dog catches up with the man we must match the equations of each one.

$d_{man}=d_{dog}$

$1.6\cdot t=3\cdot (t-1.8)$

$1.6\cdot t=3\cdot t-5.4$

$1.4\cdot t=5.4$

$t=\frac{5.4}{1.4}$

$t=3.8571s$

The result obtained previously means that the dog catches up with the man 3.8571s after the man started running.

That value is used in the man's distance equation.

$d_{man}=1.6\cdot t=1.6\cdot (3.8571)$

$d_{man}=6.1714m$

Finally, the dog catches up with the man 6.1714m later.

6 0

3 years ago

The diagram illustrates the movement of sound waves between an observer and a race car. As the race car drives away from the obs

Andrei [34K]

I believe the answer is d

6 0

3 years ago

What is the acceleration of a car that starts from rest and attains a final speed of 20 m

OlgaM077 [116]

Answer:

323.9

Explanation:

3 0

3 years ago

If i ask wat r the application of simple machine some of u will say-----> Simple machines that are widely used include the wh

TiliK225 [7]

Answer:

DID NOT

UNDER STAND

Explan it a littlebit

3 0

3 years ago

A 10 Newton effort force is required to lift a 10 kg box just off the ground. What is the effort required to lift the box off th

Karo-lina-s [1.5K]

2.0 N is the answer, I hope this helps :D

5 0

3 years ago

Read 2 more answers