All categories

3 years ago

If you speed up from rest to 12m/s in 3 seconds, what is your acceleration?

2 answers:

7 0

The answer id 4 m/s/s this is because 12/3 = 4 and an easy way to get the units is put the two together

Acceleration = m/s (Meters per second)
Time = s (Seconds)

m/s/s = Meters per second/ Per second

boyakko [2]3 years ago

6 0

b) 4m/s/s

This is because you divide the speed you reach, by the time it takes to get to that speed:

12m/s ÷ 3s = 4m/s/s

The units come from what you divide, meters per second ÷ seconds this can be written as m/s/s or ms-²

You might be interested in

When you push a 2.00 kg book resting on a tabletop it takes 4.60 N to start the book sliding. What is the coefficient of static

natali 33 [55]

The coefficient of static friction is 0.234.

Answer:

Explanation:

Frictional force is equal to the product of coefficient of friction and normal force acting on any object.

So here the mass of the object is given as 2 kg, so the normal force will be acting under the influence of acceleration due to gravity.

Normal force = mass * acceleration due to gravity

Normal force = 2 * 9.8 = 19.6 N.

And the frictional force is given as 4.6 N, then

$Coefficient of static friction = Frictional force/Normal force$

Coefficient of static friction = 4.6 N / 19.6 N = 0.234

So the coefficient of static friction is 0.234.

3 0

3 years ago

Assume that the Deschutes River has straight and parallel banks and that the current is 0.75 m/s. Drifting down the river, you f

DedPeter [7]

Answer:

d = 142.5 m

Explanation:

This is a vector exercise. Let's calculate how much the boat travels in the 40s

d₀ = $v_{b}$ t

d₀ = 0.75 40

d₀ = 30 m

Let's write the kinematic equations

Boat

x = d₀ + $v_{b}$ t

x = 0 + $v_{h}$ t

At the meeting point the coordinate is the same for both

d₀ + $v_{b}$ t = $v_{h}$ t

t ( $v_{h}$ - $v_{b}$ ) = d₀

t = d₀ / ( $v_{b}$ - $v_{h}$ )

The two go in the same direction therefore the speeds have the same sign

t = 30 / (0.95-0.775)

t = 150 s

The distance traveled by man is

d = $v_{h}$ t

d = 0.95 150

d = 142.5 m

3 0

3 years ago

What is the wavelength of an earthquake that shakes you with a frequency of 10.0 Hz and gets to another city 84.0 km away in 12.

Harrizon [31]

Answer:

700 m.

Explanation:

Wavelength: This can be defined as the distance in meter required by a wave to complete one oscillation. The S.I unit of of wavelength is meter (m).

the expression connecting velocity, frequency and wavelength is given as,

v = λf......................... Equation 1

Where v = velocity of the earthquake, λ = wavelength of the earthquake, f = frequency of the earthquake.

make λ the subject of the equation

λ = v/f ................. Equation 2

recall,

v = distance/time

v = d/t ................. Equation 2

Where d = distance, t -= time.

Given: d = 84 km = 84000 m, t = 12 s.

Substitute into equation 2

v = 84000/12

v = 7000 m/s.

Also given: f = 10 Hz.

Substitute into equation 2

λ = 7000/10

λ = 700 m.

Hence the wavelength of the earthquake = 700 m.

5 0

3 years ago

Read 2 more answers

Two loudspeakers are located 3.0 m apart on the stage of an auditorium. A listener at point P is seated 19.0 m from one speaker

Amanda [17]

Answer:

The frequencies that the listener at P will hear a maximum intensity are: 85.75 Hz, 171.5 Hz, 257.25 Hz and 343 Hz.

Explanation:

Path Difference Δx is given as: nλ

where λ = $\frac{v}{f}$

Δx can be re-written as: n× $\frac{v}{f}$

where;

n = integer

v = speed of sound = 343 m/s

f = frequency

Δx = 19.0 m - 15.0 m

Δx = 4.0 m

$4.0 m =$ $\frac{n*343}{f}$

f = $\frac{n*343}{4}$

f = n × 85.75 Hz

Now; n = 1, 2, 3, 4 ; the frequencies that the listener at P will hear the maximum intensity will be

when n= 1

f = 1 × 85.75 Hz

f = 85.75 Hz

when n= 2

f = 2 × 85.75 Hz

f = 171.5 Hz

when n= 3

f = 3 × 85.75 Hz

f = 257.25 Hz

when n= 4

f = 4 × 85.75 Hz

f = 343 Hz

∴ the frequencies that the listener at P will hear the maximum intensity will be : 85.75 Hz, 171.5 Hz, 257.25 Hz and 343 Hz for n =1,2,3, and 4 respectively.

7 0

3 years ago

A bottle of water at a room temperature of 21.0 C is placed into a refrigerator

fredd [130]

Answer:

B. in both directions until the temperature is equal in the water and the air

Explanation:

When a warm body is in contact with a cool body , there is exchange of heat energy in both sides until there is attainment of equilibrium temperature . At this temperature both the body attains equal temperature . Initially rate of heat radiated by warm body is more than that from cool body , but after attainment of equilibrium , the rate becomes equal to each other . This is called dynamic equilibrium .

Hence option B is correct .

7 0

3 years ago