All categories

3 years ago

a car travelling at 50km/h from rest covers a distance of 10km in 40minutes. Calculate the acceleration

Physics

1 answer:

Margarita [4]3 years ago

7 0

Answer:

$9.67\cdot 10^{-3}m/s^2$

Explanation:

We can solve the problem by using the following suvat equation:

$v^2-u^2=2as$

where

v is the final velocity

u is the initial velocity

a is the acceleration

s is the displacement

For the car in this problem:

u = 0 (it starts from rest)

$v=50 km/h \cdot \frac{1000}{3600}=13.9 m/s$ is the final velocity

s = 10 km = 10 000 m is the displacement

Solving for a, we find:

$a=\frac{v^2-u^2}{2s}=\frac{13.9^2}{2(10000)}=9.67\cdot 10^{-3}m/s^2$

You might be interested in

What makes silver and gold different by using the terms atom and element

djyliett [7]

Silver is classified as a <span>precious metal.

Where Gold is classified as </span><span>transition metal.

Silver has about 47 protons and Gold has way more- about 79 protons.</span>

8 0

3 years ago

A battery establishes a voltage V on a parallel-plate capacitor. After the battery is disconnected, the distance between the pla

disa [49]

Answer:

Explanation:

Since, the capacitance( decreases )

therefore voltage between the plates(increases ).

Hence, option d is correct.

C =εA/d.

d is doubled, therefore C decrease ( inverse relation).

4 0

3 years ago

A permeability test was run on a compacted sample of dirty sandy gravel. The sample was 175 mm long and the diameter of the mold

LUCKY_DIMON [66]

Answer:

(a). The coefficient of permeability is $8.6\times10^{-3}\ cm/s$ .

(b). The seepage velocity is 0.0330 cm/s.

(c). The discharge velocity during the test is 0.0187 cm/s.

Explanation:

Given that,

Length = 175 mm

Diameter = 175 mm

Time = 90 sec

Volume= 405 cm³

We need to calculate the discharge

Using formula of discharge

$Q=\dfrac{V}{t}$

Put the value into the formula

$Q=\dfrac{405}{90}$

$Q=4.5\ cm^3/s$

(a). We need to calculate the coefficient of permeability

Using formula of coefficient of permeability

$Q=kiA$

$k=\dfrac{Q}{iA}$

$k=\dfrac{Ql}{Ah}$

Where, Q=discharge

l = length

A = cross section area

h=constant head causing flow

Put the value into the formula

$k=\dfrac{4.5\times175\times10^{-1}}{\dfrac{\pi(175\times10^{-1})^2}{4}\times38}$

$k=8.6\times10^{-3}\ cm/s$

The coefficient of permeability is $8.6\times10^{-3}\ cm/s$ .

(c). We need to calculate the discharge velocity during the test

Using formula of discharge velocity

$v=ki$

$v=\dfrac{kh}{l}$

Put the value into the formula

$v=\dfrac{8.6\times10^{-3}\times38}{17.5}$

$v=0.0187\ cm/s$

The discharge velocity during the test is 0.0187 cm/s.

(b). We need to calculate the volume of solid in the ample

Using formula of volume

$V_{s}=\dfrac{M_{s}}{V_{s}}$

Put the value into the formula

$V_{s}=\dfrac{4950\times10^{-3}}{2710}$

$V_{s}=1826.56\ cm^3$

We need to calculate the volume of the soil specimen

Using formula of volume

$V=A\times L$

Put the value into the formula

$V=\dfrac{\pi(17.5)^2}{4}\times17.5$

$V=4209.24\ cm^3$

We need to calculate the volume of the voids

$V_{v}=V-V_{s}$

Put the value into the formula

$V_{v}=4209.24-1826.56$

$V_{v}=2382.68\ cm^3$

We need to calculate the seepage velocity

Using formula of velocity

$Av=A_{v}v_{s}$

$v_{s}=\dfrac{Av}{A_{v}}$

$v_{s}=\dfrac{V}{V_{v}}\times v$

Put the value into the formula

$v_{s}=\dfrac{4209.24}{2382.68}\times0.0187$

$v_{s}=0.0330\ cm/s$

The seepage velocity is 0.0330 cm/s.

Hence, (a). The coefficient of permeability is $8.6\times10^{-3}\ cm/s$ .

(b). The seepage velocity is 0.0330 cm/s.

(c). The discharge velocity during the test is 0.0187 cm/s.

8 0

3 years ago

All electric devices are required to have identifying plates that specify their electrical characteristics. The plate on a certa

masha68 [24]

Answer:

R= 20 ohm

Explanation:

Given that

Current ,I = 6 A

Voltage difference ,ΔV = 120 V

Lets take resistance of the stem iron = R

We know that ,the relationship between current ,voltage difference and resistance is given as

ΔV = I R

$R=\dfrac{\Delta V}{I}$

Now by putting the values in the above equation we get

$R=\dfrac{120}{6}\ ohm$

R= 20 ohm

Therefore the resistance of the steam will be 20 ohm.

3 0

3 years ago

Tomorrow i have a science test, could someone please fill me in on the water cycle?

Lorico [155]

the cycle of processes by which water circulates between the earth's oceans, atmosphere and land involving precipitation as rain and snow drainage in streams and rivers and return to the atmosphere by evaporation and transpiration.

Hope this gives you a little bit more information!

5 0

3 years ago

a car travelling at 50km/h from rest covers a distance of 10km in 40minutes. Calculate the acceleration​

a car travelling at 50km/h from rest covers a distance of 10km in 40minutes. Calculate the acceleration