ANSWER QUICK 30 POINTS

A 1400-kg car moving with a speed of 32 m/s is approaching a stoplight. The light turns yellow and the car makes an abrupt stop

inna [77]

Answer:

c. 716, 800 J

Explanation:

t = Time taken

u = Initial velocity = 32 m/s

v = Final velocity = 0

s = Displacement = 60 m

a = Acceleration

m = Mass of car = 1400 kg

$v^2-u^2=2as\\\Rightarrow a=\dfrac{v^2-u^2}{2s}\\\Rightarrow a=\dfrac{0^2-32^2}{2\times 60}$

Work done is given by

$W=Fscos\theta\\\Rightarrow W=mascos\theta\\\Rightarrow W=1400\times \dfrac{0^2-32^2}{2\times 60}\times 60\times cos0\\\Rightarrow W=-716800\ J$

The amount of work done to stop the car is 716800 J

8 0

3 years ago

How many changes can this undergo?Does it mean from this current state or how it can change.Please explain it to me.If you were

Fofino [41]

Let's assume this is a drawing of particles of a gas substance. This assumption is made upon the fact that these particles are not close and are represented in motion characteristic for gases. Gases can become solid by skipping the liquid phase. This process is called deposition. Also, a gas can become a liquid through the process of condensation as a result of energy loss at molecular level. Likewise, this is enabled thanks to heat loss or applied pressure.

5 0

3 years ago

Whenever two Apollo astronauts were on the surface of the Moon, a third astronaut orbited the Moon. Assume the orbit to be circu

inysia [295]

Answer:

$v = 1,582 \ \frac{m}{s}$

Explanation:

We know that for circular motion the centripetal acceleration $a_c$ is:

$a_c = \frac{v^2}{r}$

where v is the speed and r is the radius.

The centripetal acceleration for the astronaut must be the gravitational acceleration due to the gravity, as there are no other force. So

$a_c = 1.27 \frac{m}{s^2}$ .

The radius of the orbit must be the radius of the Moon, plus the 270 km above the surface

$r = 1.7 * 10^6 \ m + 270 \ km$

$r = 1.7 * 10^6 \ m + 270 * 10^3 \ m$

$r = 1.7 * 10^6 \ m + 0.270 * 10^6 \ m$

$r = 1.97 * 10^6 \ m$

We can obtain the speed as:

$v^2 = a_c r$

$v = \sqrt{a_c r}$

$v = \sqrt{1.27 \frac{m}{s^2} * 1.97 * 10^6 \ m}$

$v = \sqrt{ 2.509 \ 10^6 \ \frac{m^2}{s^2}}$

$v = 1.582 \ 10^3 \ \frac{m}{s}$

$v = 1,582 \ \frac{m}{s}$

And this is the orbital speed.

7 0

3 years ago

A 1.2 kg block of wood hangs motionless from strings. A 50 gram bullet, traveling horzontally, strikes the block and becomes emb

Firdavs [7]

Answer:

speed of the bullet before it hit the block is 200 m/s

Explanation:

given data

mass of block m1 = 1.2 kg

mass of bullet m2 = 50 gram = 0.05 kg

combine speed V= 8.0 m/s

to find out

speed of the bullet before it hit the block

solution

we will apply here conservation of momentum that is

m1 × v1 + m2 × v2 = M × V .............1

here m1 is mass of block and m2 is mass of bullet and v1 is initial speed of block i.e 0 and v2 is initial speed of bullet and M is combine mass of block and bullet and V is combine speed of block and bullet

put all value in equation 1

m1 × v1 + m2 × v2 = M × V

1.2 × 0 + 0.05 × v2 = ( 1.2 + 0.05 ) × 8

solve it we get

v2 = 200 m/s

so speed of the bullet before it hit the block is 200 m/s

8 0

3 years ago

In the chemical equation above, the small number after the O in 1202 represent —

Murrr4er [49]

Answer:

G.) The number atoms of that element in the molecule

Explanation:

F is incorrect because the coefficient represents the amount of one type of molecule, not the subscript

G is correct because subscripts represent how many atoms of that element are present in that single molecule

H is incorrect because energy is not represented in this simple type of equation

J is incorrect because it doesn't even make sense

7 0

3 years ago