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
myrzilka [38]
4 years ago
14

A boat in a race accelerates uniformly at 0.2 m/s² for 18 seconds to reach a final speed of 6 m/s. Work out the initial speed of

the boat.
Physics
1 answer:
Xelga [282]4 years ago
4 0

Answer:

initial velocity=2.4m/s

Explanation:

Using the formula:

v=u+at

v= final velocity (6m/s)

u=initial velocity (???)

a=acceleration (0.2 m/s²)

t=time(18 seconds)

v=u+at

6=u+(0.2*18)

6=u+3.6

u=6-3.6

u (initial velocity)=2.4m/s

You might be interested in
Which of the following is a graph of the velocity of an object as it falls fromrest if drag is not ignored? Explain your choice
MariettaO [177]

The air drag is a force that depends on the speed of an object relative to the wind. Under certain conditions, it can be modeled as:

F=-bv

Where b is a constant.

As a falling object reaches a speed so that its weight is cancelled out by the air drag, the object will reach a maximum velocity.

In a speed vs time gaph, the speed would approach the maximum speed like an asymptote.

On the other hand, since the object falls from rest, the initial speed on the graph must be zero.

Taking these considerations into account, the correct graph for the movement of an object that falls from rest if air drag is not ignored, is option B.

7 0
1 year ago
Which would take more force to stop in 17. 3 seconds: a 3. 2 kg ball rolling in a straight line at a speed of 0. 3 m/sec or a 4.
Molodets [167]
The second one (4.1 kg ball)

This is because the mxv is greater than the other one.

For the 4.1kg ball, the force it’s moving on is 4.92N

As for the 3.2kg ball, it’s moving with a force of 0.9N. Much less than the other one.
4 0
2 years ago
If a force does a positive amount of work on an object, does the object’s speed increase, decrease, or remain the same? Justify
iris [78.8K]

Answer:

see that there is no dependence on speed, so the work remains constant

Explanation:

Work is defined by the expression

        W = F. d

where the boldface indicates vectors, this equation can be written in scalar form

         W = f d cos θ

where θ is the angle between force and displacement.

We see that there is no dependence on speed, so the work remains constant

The power is

           P = W / t

           P = f d / t

           p = F v

we see that the power is the one that depends on the speed of the body

6 0
3 years ago
1) A crane uses an average force of 5,200 N to lift a girder 25 m. How much work does the crane do on the girder?
Andrej [43]

Answer:

1) 130, 000 J

2) 1 J

Explanation:

1)

Work done is product of force in Newtons and distance in meters

W=Fd

Given an average force of 5,200 N and distance of 25 m then we evaluate that

Work done=5200*25=130, 000 Nm or Joules

2)

Similarly, for the second question, given force of 1N and distace of 1 m then the work done will be

W=1*1=1 J

8 0
3 years ago
How to calculate motion​
otez555 [7]

Answer:

Distnace per unit time

Explanation:

3 0
3 years ago
Read 2 more answers
Other questions:
  • Water drops from the nozzle of a shower onto the floor 81 inches below. The drops fall at regular intervals of time, the first d
    13·1 answer
  • Whats a dominant allele
    11·2 answers
  • Given the resistivities below, which matedal is best described as an insulator?
    8·1 answer
  • The navigation lights of some aircraft consist of a single circuit controlled by a single switch which has an ON position and an
    15·1 answer
  • A total electric charge of 3.50 nC is distributed uniformly over the surface of a metal sphere with a radius of 24.0 cm. If the
    12·1 answer
  • A dragster accelerated to a speed of 112m/s over a distance of 398m. Determine the acceleration (assume uniform) of the dragster
    7·1 answer
  • A bag of sand has a density of 45 g/cm3 and a mass of 15 kg. How much space does the sand take up?
    15·2 answers
  • A toy car has a kinetic energy of 8 J. What is its kinetic energy after a frictional force of 0.5 N has acted on it for 6 m?
    9·1 answer
  • Describe several characteristics that distinguish population I stars from population II stars.
    9·1 answer
  • What do protoplanets eventually grow into?​
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!