Match each chemical name with the correct chemical formula.

A 62.2-kg person, running horizontally with a velocity of 3.80 m/s, jumps onto a 19.7-kg sled that is initially at rest. (a) Ign

jek_recluse [69]

Answer:

a) $v = 2.886\,\frac{m}{s}$ , b) $\mu_{k} = 0.014$

Explanation:

a) The final speed is determined by the Principle of Momentum Conservation:

$(62.2\,kg)\cdot (3.80\,\frac{m}{s} ) = (81.9\,kg)\cdot v$

$v = 2.886\,\frac{m}{s}$

b) The deceleration experimented by the system person-sled is:

$a = \frac{\left(0\,\frac{m}{s} \right)^{2}-\left(2.886\,\frac{m}{s} \right)^{2}}{2\cdot (30\,m)}$

$a = -0.139\,\frac{m}{s^{2}}$

By using the Newton's Laws, the only force acting on the motion of the system is the friction between snow and sled. The kinetic coefficient of friction is:

$-\mu_{k}\cdot m\cdot g = m\cdot a$

$\mu_{k} = -\frac{a}{g}$

$\mu_{k} = -\frac{\left(-0.139\,\frac{m}{s^{2}} \right)}{9.807\,\frac{m}{s^{2}} }$

$\mu_{k} = 0.014$

3 0

3 years ago

PLEASE HELP!! ITS URGENT!!!

Natasha2012 [34]

Answer:

F = 800 [N]

Explanation:

To be able to calculate this problem we must use the principle of momentum before and after the impact of the hammer.

We must summarize that after the impact the hammer does not move, therefore its speed is zero. In this way, we can propose the following equation.

ΣPbefore = ΣPafter

$(m_{1}*v_{1}) - F*t = (m_{1}*v_{2})$

where:

m₁ = mass of the hammer = 0.15 [m/s]

v₁ = velocity of the hammer = 8 [m/s]

F = force [N] (units of Newtons)

t = time = 0.0015 [s]

v₂ = velocity of the hammer after the impact = 0

$(0.15*8)-(F*0.0015) = (0.15*0)\\F*0.0015 = 0.15*8\\F = 1.2/(0.0015)\\F = 800 [N]$

Note: The force is taken as negative since it is exerted by the nail on the hammer and this force is directed in the opposite direction to the movement of the hammer.

6 0

3 years ago

If 400 N of force was applied to a rock and it had an acceleration of 20 ms2 , what is the mass of rock?

Troyanec [42]

Answer:

Explanation:

The mass of the rock can be found by using the formula

$m = \frac{f}{a} \\$

f is the force

a is the acceleration

From the question we have

$m = \frac{400}{20} = \frac{40}{2} \\$

We have the final answer as

Hope this helps you

5 0

3 years ago

1. How much energy is needed to raise 1 g of water 1°C?

Serga [27]

Answer:

1.The calorie was originally defined as the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1 gram of water 1° Celsius. Since 1925 this calorie has been defined in terms of the joule, the definition since 1948 being that one calorie is equal to approximately 4.2 joules.

2.Boiling water at 100 degrees Celsius: 540 calories are needed to turn 1 gram (at 100 degrees Celsius) of water to steam.

5 0

4 years ago

A baseball goes from zero to 38 m/s in 0.157 s. what is its average acceleration? answer in units of m/s 2 .

Likurg_2 [28]

Since acceleration is measured in whole seconds, you need to know how many times 0.157seconds goes into 1 second... (just divide 1 by 0.157) = 6.369

So if in 0.157seconds the baseball went from zero to 38m/s, then to find out how fast it would be traveling after one whole second just multiply 38m/s by 6.369

38m/s x 6.369 = 242.038 m/s^2

3 0

3 years ago