Ask question

Ask question

All categories

3 years ago

7

Density is mass / volume. (D = m/V) A loaf of bread has a volume of 2270 cm3 and a mass of 454 g. What is the density of the bre

ad?g/cm3

1 answer:

Shkiper50 [21]3 years ago

3 0

Answer: 0.2 g/cm3

Explanation:

Density = m/V

m= 454 g

V= 2270 cm3

D = 454 g/2270 cm3

D = 0.2 g/cm3

You might be interested in

Why does the Moon seem to change shape?

Licemer1 [7]

Answer:

A

Explanation:

3 0

3 years ago

Read 2 more answers

This type of reaction is most like breaking a rack of balls at the start of a game of pool:

Svet_ta [14]

The answer is b fission hope this helps

5 0

4 years ago

A car moves forward up a hill at 12 m/s with a uniform backward acceleration of 1.6 m/s2. What is its displacement after 6 s?

Romashka [77]

Answer:

The displacement of the car after 6s is 43.2 m

Explanation:

Given;

velocity of the car, v = 12 m/s

acceleration of the car, a = -1.6 m/s² (backward acceleration)

time of motion, t = 6 s

The displacement of the car after 6s is given by the following kinematic equation;

d = ut + ¹/₂at²

d = (12 x 6) + ¹/₂(-1.6)(6)²

d = 72 - 28.8

d = 43.2 m

Therefore, the displacement of the car after 6s is 43.2 m

6 0

3 years ago

A 2000 kg car moves along a horizontal road at speed vo

cluponka [151]

Answer:

The shortest possible stopping distance of the car is 175.319 meters.

Explanation:

In this case we see that driver use the brakes to stop the car by means of kinetic friction force. Deceleration of the car is directly proportional to kinetic friction coefficient and can be determined by Second Newton's Law:

$\Sigma F_{x} = -\mu_{k}\cdot N = m \cdot a$ (Eq. 1)

$\Sigma F_{y} = N-m\cdot g = 0$ (Eq. 2)

After quick handling, we get that deceleration experimented by the car is equal to:

$a = -\mu_{k}\cdot g$ (Eq. 3)

Where:

$a$ - Deceleration of the car, measured in meters per square second.

$\mu_{k}$ - Kinetic coefficient of friction, dimensionless.

$g$ - Gravitational acceleration, measured in meters per square second.

If we know that $\mu_{k} = 0.0735$ and $g = 9.807\,\frac{m}{s^{2}}$ , then deceleration of the car is:

$a = -(0.0735)\cdot (9.807\,\frac{m}{s^{2}} )$

$a = -0.721\,\frac{m}{s^{2}}$

The stopping distance of the car ( $\Delta s$ ), measured in meters, is determined from the following kinematic expression:

$\Delta s = \frac{v^{2}-v_{o}^{2}}{2\cdot a}$ (Eq. 4)

Where:

$v_{o}$ - Initial speed of the car, measured in meters per second.

$v$ - Final speed of the car, measured in meters per second.

If we know that $v_{o} = 15.9\,\frac{m}{s}$ , $v = 0\,\frac{m}{s}$ and $a = -0.721\,\frac{m}{s^{2}}$ , stopping distance of the car is:

$\Delta s = \frac{\left(0\,\frac{m}{s} \right)^{2}-\left(15.9\,\frac{m}{s} \right)^{2}}{2\cdot \left(-0.721\,\frac{m}{s^{2}} \right)}$

$\Delta s = 175.319\,m$

The shortest possible stopping distance of the car is 175.319 meters.

8 0

4 years ago

When two objects interact, the change in momentum of the first object is ______ the change in momentum of the second object.

Mariulka [41]

Answer:

A. Equal to and Opposite

Explanation:

when there is no External force acting on the system of bodies then Net momentum of the system is Conserved .

Given that there are 2 bodies

Let P₁ as first object's momentum

P₂ as second object's momentum.

Total Momentum =P₁ + P₂

As there is no external force acying on the system

Change in the Total momentum is zero

so,

0 = Δ P₁ + ΔP₂

ΔP₂ = -ΔP₁

negative sign indicates opposite direction.

Both are of equal magnitude.

6 0

4 years ago