1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
nadya68 [22]
3 years ago
14

A 45 kg boy runs at a rate of 2.5 m/s and jumps on top of a stationary skateboard that has a mass of 4 kg. After jumping onto th

e board, the boy and the board travel off together. Assuming that momentum is conserved, what is the final speed of the boy and the board?
Physics
2 answers:
Natalija [7]3 years ago
7 0

Answer:

v = 2.29 m/s

Explanation:

As we know that the external force on the system of mass of boy + board is ZERO

So here we can use momentum conservation

now we have

m_1v_1 + m_2v_2 = (m_1 + m_2) v

now we have

45 (2.5) + 4(0) = (45 + 4) v

now we have

v = \frac{45}{49} (2.5)

v = 2.29 m/s

igomit [66]3 years ago
4 0

Answer:

V = 2.29 m/s

Explanation:

Given that,

Mass of the boy, m_1=45\ kg

Mass of the skateboard, m_2=4\ kg                            

Initial speed of the boy, v = 2.5 m/s

Let V is the final velocity of the boy and the board. The net momentum of the system remains constant. Using the conservation of linear momentum to find it as :

45\times 2.5=(45+4)V

V=\dfrac{45\times 2.5}{(45+4)}

V = 2.29 m/s

So, the velocity of the boat after Batman lands in it 2.29 m/s. Hence, this is the required solution.                                                                

You might be interested in
Zero, a hypothetical planet, has a mass of 4.5 x 1023 kg, a radius of 3.2 x 106 m, and no atmosphere. A 10 kg space probe is to
jok3333 [9.3K]

a.) K 2=K 1 +GmM( r 21− r 11)=2.2×10 7J

b.) ​K 2 +GmM( r 11− r 21)=6.9×10 7 J

Applying Law of  Energy conservation :

K 1+U 1

=K 2+U 2

⇒K 1− r 1GmM

=K 2− r 2 GmM

where M=5.0×10 23kg,r1

=> R=3.0×10 6m and m=10kg

(a) If K 1​

=5.0×10 7J and r 2

=4.0×10 6 m, then the above equation leads to

K 2=K 1 +GmM (r 21− r 11)=2.2×10 7J

(b) In this case, we require K 2

=0 and r2

=8.0×10 6m, and solve for K 1:K 1

​=K 2 +GmM (r 11− r 21)=6.9×10 7 J

Learn more about Kinetic energy on:

brainly.com/question/12337396

#SPJ4

7 0
2 years ago
Suppose the coefficient of static friction between a quarter and the back wall of a rocket car is 0.383. At what minimum rate wo
djverab [1.8K]

Answer:

25.59 m/s²

Explanation:

Using the formula for  the force of static friction:

f_s = \mu_s N --- (1)

where;

f_s = static friction force

\mu_s = coefficient of static friction

N = normal force

Also, recall that:

F = mass × acceleration

Similarly, N = mg

here, due to min. acceleration of the car;

N = ma_{min}

From equation (1)

f_s = \mu_s ma_{min}

However, there is a need to balance the frictional force by using the force due to the car's acceleration between the quarter and the wall of the rocket.

Thus,

F = f_s

mg = \mu_s ma_{min}

a_{min} = \dfrac{mg }{ \mu_s m}

a_{min} = \dfrac{g }{ \mu_s }

where;

\mu_s = 0.383 and g = 9.8 m/s²

a_{min} = \dfrac{9.8 \ m/s^2 }{0.383 }

\mathbf{a_{min}= 25.59 \ m/s^2}

3 0
3 years ago
You want to set up an aquarium and need to determine what size tank to buy. The graph shows tank sizes using a rule that relates
sineoko [7]

connexus unit 8 lesson 1 PRACTICE!

1) B

2) C

3) A

4) C

5) B

6) A

7) D  

8) A

9) D  

10) A

11) A

12) C

13) D

14) C

15) B

16) B

Hope this helps you guys out!

4 0
3 years ago
Read 2 more answers
A time-dependent but otherwise uniform magnetic field of magnitude B0(t) is confined in a cylindrical region of radius 6.5 cm. I
Papessa [141]

Answer:

The acceleration is   a = 3.45*10^{3} m/s^2

Explanation:

 From the question we are told that

         The radius is  d = 6.5 cm = \frac{6.5}{100} = 0.065 m

           The magnitude of the magnetic field is  B = 5.5 T

           The rate at which it decreases is  \frac{dB}{dt}  = 24.5G/s = 24.5*10^{-4} T/s

             The distance from the center of field is  r = 1.5 cm = \frac{1.5}{100} = 0.015m

  According to Faraday's law

          \epsilon = - \frac{d \o}{dt}

and   \epsilon = \int\limits  {E} \, dl

 Where  the magnetic flux \o = B* A

             E is the electric field  

             dl is a unit length

 So

         \int\limits  {E} \, dl = - \frac{d}{dt} (B*A)

         {E}  l = - \frac{d}{dt} (B*A)

Now l is the circumference of the circular loop formed by the magnetic field and it mathematically represented as  l = 2\pi r

A is the area  of the circular loop formed by the magnetic field and it mathematically represented as  A= \pi r^2

So

    {E}  (2 \pi r)= -  \pi r^2 \frac{dB}{dt}

    E = \frac{r}{2} [ - \frac{db}{dt} ]  

Substituting values  

    E = \frac{0.015}{2} (24*10^{-4})

         E = 3.6*10^{-5} V/m

The negative signify the negative which is counterclockwise

 

  The force acting on the proton is mathematically represented as

                       F_p = ma

        Also       F_p = q E

So

           ma = qE

 Where m is the mass of the the proton which has a value of  m = 1.67 *10^{-27} kg

 q = 1.602 *10^{-19} C

     So

            a =\frac{1.60 *10^{-19} *(3.6 *10^{-5}) }{1.67 *10^{-27}}

               a = 3.45*10^{3} m/s^2

                   

     

               

8 0
3 years ago
List 3 different thermometers made based on their uses.<br> help please
My name is Ann [436]

Answer:

Digital thermometers.

Electronic ear thermometers.

Forehead thermometers.

Explanation:

7 0
3 years ago
Other questions:
  • Which of the following is not conserved?
    8·1 answer
  • Why is electricity dead buy solar panels fundamentally different from converting thermal energy into electricity? (Bet you can't
    8·1 answer
  • What is the difference between a dry cell and a wet cell?​
    12·1 answer
  • What must be the normal force acting on a crate as it slides across a horizontal floor if the friction acting on the box is 0.49
    7·1 answer
  • How much time will it take for a bug to travel 5 meters across the floor if it is traveling at 1 m/s?
    12·1 answer
  • The average distance between the earth and the sun is defined as being one
    5·1 answer
  • A machine is applying a torque to rotationally accelerate a metal disk during a manufacturing process. An engineer is using a gr
    8·2 answers
  • If galaxy A is 800 million light years away and galaxy B is 1500 million light
    14·1 answer
  • Can you please answer theese two qeastion
    6·1 answer
  • Line segment Q R , Line segment R S and Line segment S Q are midsegments of Î"WXY. Triangle R Q S is inside triangle X Y W. Poin
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!