Which animal have no teeth

A 40 kg girl and an 8.4 kg sled are on the surface of a frozen lake, 15 m apart. By means of a rope, the girl exerts a 5.2 N for

stealth61 [152]

Answer:

(a) $a_s=0.62\frac{m}{s^2}$

(b) $a_s=0.13\frac{m}{s^2}$

(c) $x_f=2.6m$

Explanation:

(a) According to Newton's second law, the acceleration of a body is directly proportional to the force exerted on it and inversely proportional to it's mass.

$a_s=\frac{F}{m_s}\\a_s=\frac{5.2N}{8.4kg}\\a_s=0.62\frac{m}{s^2}$

(b) According to Newton's third law, the force that the sled exerts on the girl is equal in magnitude but opposite in the direction of the force that the girl exerts on the sled:

$a_g=\frac{F}{m_g}\\a_g=\frac{5.2N}{40kg}\\a_g=0.13\frac{m}{s^2}$

(c) Using the kinematics equation:

$x_f=x_0+v_0t \pm \frac{at^2}{2}$

For the girl, we have $x_0=0$ and $v_0=0$ . So:

$x_f_g=\frac{a_gt^2}{2}(1)$

For the sled, we have $v_0=0$ . So:

$x_f_s=x_0_s-\frac{a_st^2}{2}(2)$

When they meet, the final positions are the same. So, equaling (1) and (2) and solving for t:

$x_0_s-\frac{a_st^2}{2}=\frac{a_st^2}{2}\\t^2(a_g+a_s)=2x_0_s\\t=\sqrt{\frac{2x_s_0}{a_g+a_s}}\\t=\sqrt{\frac{2(15m)}{0.13\frac{m}{s^2}+0.62\frac{m}{s^2}}}\\t=6.32s$

Now, we solve (1) for $x_f_g$

$x_f_g=\frac{0.13\frac{m}{s^2}(6.32s)^2}{2}\\x_f_g=2.6m\\x_f=2.6m$

5 0

3 years ago

Spend time observing or thinking about events that involve matter and energy. Which events can you explain? Which event's can't

Ipatiy [6.2K]

Eating. Your muscles in your arms and mouth use energy to feed itself. Then your body digest the food which also takes energy.

Sleep. When your tired, you don’t have much energy. It is said that you use more energy while your sleeping. But how do you become energized if you were using even more energy than before?

7 0

3 years ago

Read 2 more answers

What is the cell emf for the concentrations given? Express your answer using two significant figures.

alisha [4.7K]

Complete Question

A voltaic cell is constructed with two $Zn^{2+}$ $- Zn$ electrodes. The two cell compartment have $[Zn^{2+}] = 1.6 \ M$ and $[Zn^{2+}] = 2.00*10^{-2} \ M$ respectively.

What is the cell emf for the concentrations given? Express your answer using two significant figures

Answer:

The value is $E = 0.06 V$

Explanation:

Generally from the question we are told that

The concentration of $[Zn^{2+}]$ at the cathode is $[Zn^{2+}]_a = 1.6 \ M$

The concentration of $[Zn^{2+}]$ at the anode is $[Zn^{2+}]_c = 2.00*10^{-2} \ M$

Generally the the cell emf for the concentration is mathematically represented as

$E = E^o - \frac{0.0591}{2} log\frac{[Zn^{2+}]a}{ [Zn^{2+}]c}$

Generally the $E^o$ is the standard emf of a cell, the value is 0 V

So

$E = 0 - \frac{0.0591}{2} * log[\frac{ 2.00*10^{-2}}{1.6} ]$

=> $E = 0.06 V$

4 0

3 years ago

which best describes the big bang theory ? A. matter was compressed into a single point and then exploded outward to form the un

Furkat [3]

Answer:

A. matter was compressed into a single point and then exploded outward to form the universe

Explanation:

The big bang is how astronomers explain the way the universe began. It is the idea that the universe began as just a single point, then expanded and stretched to grow as large as it is right now (and it could still be stretching).

6 0

4 years ago

Light of wavelength 645 nm is incident on a double slit. The angle between the central bright fringe and the second dark fringe

kumpel [21]

Answer:

Slit separation, $d=1.13\times 10^{-5}\ m$