All categories

3 years ago

A dog runs with an initial velocity of 7.5 m/s on a waxed floor. It slides to a stop in 15 seconds. What is the acceleration?

Physics

1 answer:

Leni [432]3 years ago

3 0

Answer:

-0.5 m/s^2

Explanation:

Acceleration = change in velocity / total time

7.5 / 15 = 0.5

You might be interested in

The capacity of a storage battery, such as those used in automobile electrical systems, is rated in ampere-hours (A⋅h). A 50 A⋅h

timurjin [86]

Answer:

2.80 MJ

Explanation:

(a) We want to calculate the energy U of the battery, where its voltage is E = 13.0V and the supplied current is I = 60 A. We can neglect the internal resistance, so the terminal voltage equals the emf of the battery V = 13.0V. The quantity of delivered energy is given by the rate at which energy is delivered to it in a certain time t. We could obtain the rate at which energy is transferred by using equation , where the rate represents the power P = IV. Therefore, the energy produced is given by

U = P*t (P = IV)

U = I*V*t (1)

Now we can plug our values for I, V and t into equation (1) to get the energy produced in time t = 1 h = 3600 s

U = I*V*t = (60 A)(13 V)(3600s) = 2.80 MJ

5 0

4 years ago

You are standing on a log and a friend is trying to knock

WINSTONCH [101]

Answer: catching the ball is a better choice.

Explanation:

The collision of 2 objects involves involves large impact force since the force is inversely proportional to the time in which the momentum of the object changes.

Mathematically

$F=\frac{\Delta p}{\Delta t}$

If we catch the ball we increase the time in which the momentum of the ball is decreased thus the impact force that acts on us is lower as larger time is allowed for the ball to decrease it's momentum.

If we allow the ball to hit us the momentum of the ball changes in a short period of time thus applying a large impact force on our body thus increasing the chances of toppling.

3 0

3 years ago

Isla made ice by putting water in the freezer. Freezing is an example of (2 points)

SSSSS [86.1K]

Answer:

a physical change

6 0

3 years ago

Read 2 more answers

Notice that in each conversion factor the numerator equals the denominator when units are taken into account. A common error in

navik [9.2K]

Answer:

he factor for the temporal part 1.296 107 s² = h²

m / s² = 12960 km / h²

Explanation:

This is a unit conversion exercise.

In the unit conversion, the size of the object is not changed, only the value with respect to which it is measured is changed, for this reason in the conversion the amount that is in parentheses must be worth one.

In this case, it is requested to convert a measure km/h²

Unfortunately, it is not clearly indicated what measure it is, but the most used unit in physics is m / s² , which is a measure of acceleration. Let's cut this down

the factor for the distance is 1000 m = 1 km

the factor for time is 3600 s = 1 h

let's make the conversion

m / s² (1km / 1000 m) (3600 s / 1h)²

note that as time is squared the conversion factor is also squared

m / s² = 12960 km / h²

the factor for the temporal part 1.29 107 s² = h²

6 0

3 years ago

Gravity pulls downward on a rock with a force of 800 N. If you pull upward on the rock with a force of 400 N, what is the total

wel

The answer is
a. 400 N downward

3 0

3 years ago

Read 2 more answers