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
12345 [234]
3 years ago
8

During a collision, a bus runs into a skateboarder inelastically. If the mass of the skateboarders is 70 kg and is moving at 12

m/s to the right, what is the final velocity of the skateboarder if the 2000 kg bus is traveling at 25 m/s to the left before the collision?
Physics
1 answer:
agasfer [191]3 years ago
5 0

The final velocity of the skateboarder is 23.75 m/s.

We can use conservation of momentum to calculate the magnitude of the final velocity.

Momentum before collision is equal to the momentum after collision

m1v1+m2v2=(m1+m2)v

here, v is final velocity of the skateboarder, assuming right side velocity as positive, and left side velocity as negative.

70*12+2000*(-25)=(70+2000)v

v=-23.75 m/s

Here, negative sign indicates that both skyboarder and bus will move in left direction.

You might be interested in
the kinetic energy of an object with mass m moving with a velocity of 5 m/s is 25 j what will be its kinetic energy when its vel
Dmitriy789 [7]

Answer:

100 J, 225 J

Explanation:

The kinetic energy of an object is given by:

K=\frac{1}{2}mv^2

where

m is the mass of the object

v is the velocity of the object

In this problem, the initial kinetic energy of the object is

K = 25 J

Then, the velocity is doubled, which means

v' = 2v

Therefore, the new kinetic energy will be

K'=\frac{1}{2}m(2v)^2 = 4(\frac{1}{2}mv^2)=4K

Therefore, the kinetic energy has quadrupled:

K' = 4(25)=100 J

Later, the velocity is tripled, which means

v'' = 3v

Therefore, the new kinetic energy will be

K''=\frac{1}{2}m(3v)^2 = 9(\frac{1}{2}mv^2)=9K

Therefore, the kinetic energy has increased by a factor of 9:

K' = 9(25)=225 J

4 0
3 years ago
Study the velocity vs. time graph shown.
Sindrei [870]

Answer:24m

Explanation:

5 0
3 years ago
A 4-lb ball b is traveling around in a circle of radius r1 = 3 ft with a speed (vb)1 = 6 ft>s. if the attached cord is pulled
Leya [2.2K]
Position #1:
radius, r₁ = 3 ft
Tangential speed, v₁ = 6 ft/s

By definition, the angular speed is
ω₁ = v₁/r₁ = (3 ft/s) / (3 ft) = 1 rad/s

Position #2:
Radius, r₂ = 2 ft

By definition, the moment of inertia in positions 1 and 2 are respectively
I₁ = (4 lb)*(3 ft)² = 36 lb-ft²
I₂ = (4 lb)*(2 ft)² = 16 lb-ft²

Because momentum is conserved,
I₁ω₁ = I₂ω₂
Therefore the angular velocity in position 2 is
ω₂ = (I₁/I₂)ω₁
      = (36/16)*1 = 2.25 rad/s
The tangential velocity in position 2 is
v₂ = r₂ω₂ = (2 ft)*(225 rad/s) = 4.5 ft/s

At each position, there is an outward centripetal force.
In position 1, the centripetal force is
F₁ = m*(v²/r₂) = (4)*(6²/3) = 48 lbf
In position 2, the centripetal force is
F₂ = (4)*(4.5²/2) = 40.5 lbf

The radius diminishes at a rate of 2 ft/s.
Therefore the force versus distance curve is as shown below.

The work done is the area under the curve, and it is
W = (1/2)*(48.0+40.5 ft)*(3-2 ft) = 44.25 ft-lb

Answer:  44.25 ft-lb


6 0
3 years ago
Does this marble have potential energy?<br> 1) no<br> 2)yes
jek_recluse [69]

Answer:

yes

Explanation:

because it has the potential to move

5 0
3 years ago
Can someone give me tips for science camp!! Please
Kamila [148]
Try to have a calm morning before camp. A good night’s sleep and a good breakfast. Make sure to be cautious, follow all the rules for certain areas ( some maybe restricted ). Take lots of photos doing wacky stuff! Learn but have fun learning
5 0
3 years ago
Read 2 more answers
Other questions:
  • What are the divisions within a shell called
    13·1 answer
  • 10. The shape of the earth is<br> A taco<br> b. A carrot<br> C. A sphere<br> d. A potato
    10·1 answer
  • Por favor. Escribe en Notación científica las siguientes medidas:
    9·1 answer
  • Which best explains parrallel forces
    12·1 answer
  • The area of the maxila where the teeth attach is called the ??
    8·1 answer
  • The temperature of 2.0 g of helium is increased at constant volume by ΔT. What mass of oxygen can have its temperature increased
    15·1 answer
  • A convex mirror is used in automobiles to have a Clear View of the traffic behind? give reason​
    12·1 answer
  • Match each vocabulary word with the correct definition. 1. measure of how quickly velocity is changing 2. speed in a given direc
    7·2 answers
  • 3.
    14·1 answer
  • 5. Name one career in the health and fitness field that interests you.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!