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
SpyIntel [72]
3 years ago
8

A 50kg boy jumps off the back of a 4 kg skateboard moving forward. Find the skateboard’s velocity immediately after the boy jump

s, assuming that the skateboard’s initial velocity is 5 m/s and the boy’s velocity when jumping off the back is 2.5 m/s in the forward direction.
Physics
1 answer:
AleksAgata [21]3 years ago
6 0

The mass of the boy and skateboard is there to throw you off. X and Y velocities are independent of each other, meaning that the only things you need are the velocity of the skateboard and the velocity of the boy. The total velocity of the boy is 7.5 m/s because the boy would still be moving with the 5 m/s that the skateboard has if the boy were to just jump straight up. Since the boy jumps forward with a velocity of 2.5 m/s, you would add them together.

You might be interested in
What happens when red, blue, and green light come together?
Alja [10]

Answer:

I believe if red, blue, and green light come together it would produce White light.

8 0
2 years ago
Read 2 more answers
Someone help me! you get 27 points if you get it right
pashok25 [27]

Answer:

1. D

2. D

3. A

The reason why your body goes right and the car car goes left is because your body tries to stay where it was, which is on the right. Your upper body doesn't feel a force and because of that continues in the same direction. Your lower half is pulled out from under you by seat friction to the left, leaving you leaning to the right.

8 0
2 years ago
Which planet weighs twice as much as all other planets.
Bumek [7]

Answer:

Jupiter. Although it is a gas planet, it has a ton of mass. Mass can determine the weight of an object. We can thereby assume that Jupiter weighs way more than most planets.

8 0
2 years ago
Using the law of conservation of angular momentum, estimate how fast a collapsed stellar core would spin if its initial spin rat
Nataly_w [17]

Answer:

\omega_{f} = 1000000\,\frac{rev}{day}

Explanation:

The law of conservation of angular momentum states that angular momentum remains constant when there is no external moment or forces applied to the system. Let assume that star can be modelled as an sphere, then:

\frac{2}{5}\cdot M\cdot R_{o}^{2} \cdot \omega_{o} = \frac{2}{5}\cdot M\cdot R_{f}^{2} \cdot \omega_{f}

The final angular speed is:

\omega_{f} = \omega_{o}\cdot (\frac{R_{o}}{R_{f}})^{2}

\omega_{f} = (1\,\frac{rev}{day} )\cdot (\frac{10000\,km}{10\,km} )^{2}

\omega_{f} = 1000000\,\frac{rev}{day}

3 0
2 years ago
1. Do alto de uma plataforma com 15m de altura, é lançado horizontalmente um projéctil. Pretende-se atingir um alvo localizado n
sveta [45]

Answer:

(a). The initial velocity is 28.58m/s

(b). The speed when touching the ground is 33.3m/s.

Explanation:

The equations governing the position of the projectile are

(1).\: x =v_0t

(2).\: y= 15m-\dfrac{1}{2}gt^2

where v_0 is the initial velocity.

(a).

When the projectile hits the 50m mark, y=0; therefore,

0=15-\dfrac{1}{2}gt^2

solving for t we get:

t= 1.75s.

Thus, the projectile must hit the 50m mark in 1.75s, and this condition demands from equation (1) that

50m = v_0(1.75s)

which gives

\boxed{v_0 = 28.58m/s.}

(b).

The horizontal velocity remains unchanged just before the projectile touches the ground because gravity acts only along the vertical direction; therefore,

v_x = 28.58m/s.

the vertical component of the velocity is

v_y = gt \\v_y = (9.8m/s^2)(1.75s)\\\\{v_y = 17.15m/s.

which gives a speed v of

v = \sqrt{v_x^2+v_y^2}

\boxed{v =33.3m/s.}

4 0
2 years ago
Other questions:
  • Two objects are moving at equal speed along a level, frictionless surface. the second object has twice the mass of the first obj
    6·1 answer
  • Where would a car traveling on a roller coaster have the most potential energy
    5·1 answer
  • In what direction would the particles in this wave move, relative to the direction of wave travel?
    7·2 answers
  • The following are possible ways to express the quantity 0.391 (Give ALL correct answers, i.e., B, AC, BCD...) Note: 3.45E-8 is a
    9·1 answer
  • How do hurricanes differ from tornadoes?
    12·1 answer
  • What is one example of thermal energy
    10·1 answer
  • Doubling an object’s height will have what effect on its potential energy due to gravity?
    11·1 answer
  • Molecules can be made of atoms of__?
    6·2 answers
  • You are taking the elevator to 10th floor. Are you in motion.
    5·1 answer
  • You have a piece of cork with a volume of 2 cm^3 and a density of 210kg/m^3. You hold it under water and release it.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!