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
Vera_Pavlovna [14]
3 years ago
11

The speed of a tennis ball that is served is 73.14 m/s. During a serve, the ball typically starts from rest and is in contact wi

th the tennis racquet for 30 milliseconds. Assuming constant acceleration, what is the average force exerted on the tennis ball during the serve, expressed in terms of the ball’s weight w?
450w
150w
250w
350w
Physics
1 answer:
Serga [27]3 years ago
3 0

Answer: Third option

F = 250w

Explanation:

The impulse can be written as the product of force for the time interval in which it is applied.

I = F (t_2-t_1)

You can also write impulse I as the change of the linear momentum of the ball

I = mv_2 -mv_1

So:

F (t_2-t_1) = mv_2 -mv_1

We want to find the force applied to the ball. We know that

(t_2-t_1) = 30 milliseconds = 0.03 seconds

The initial velocity v_1 is zero.

The final speed v_2 = 73.14\ m / s

So

F * 0.03 = 73.14m

F * 0.03 = 73.14m\\\\F=\frac{73.14m}{0.03}\\\\F=2438m

We must express the result of the force in terms of the weight of the ball.

We divide the expression between the acceleration of gravity

g = 9.8\ m / s ^ 2

F=\frac{2438m*g}{g},\ \ m*g=w\\\\g=9.8\ m/s^2\\\\F=\frac{2438w}{9.8}\\\\F=249w

The answer is the third option

You might be interested in
Answer this please. thanks in advance!! please tel me                                                                 a christma
saw5 [17]
If 50 identical light bulbs are connected in series across
a single power source, then the voltage across each bulb
is ( 1/50 ) of the voltage delivered by the power source.
6 0
4 years ago
Read 2 more answers
A fuel pump sends gasoline from a car's fuel tank to the engine at a rate of 5.64 10-2 kg/s. the density of the gasoline is 735
Irina18 [472]
Given:
Gasoline pumping rate, R = 5.64 x 10⁻² kg/s
Density of gasoline, D = 735 kg/m³
Radius of fuel line, r = 3.43 x 10⁻³ m

Calculate the cross sectional area of the fuel line.
A = πr² = π(3.43 x 10⁻³ m)² = 3.6961 x 10⁻⁵ m²

Let v =  speed of pumping the gasoline, m/s
Then the mass flow rate is 
M = AvD = (3.6961 x 10⁻⁵ m²)*(v m/s)*(735 kg/m³) = 0.027166v kg/s

The gasoline pumping rate is given as 5.64 x 10⁻² kg/s, therefore
0.027166v = 0.0564
v = 2.076 m/s

Answer:  2.076 m/s
The gasoline moves through the fuel line at 2.076 m/s.
7 0
3 years ago
Read 2 more answers
An object dropped on Planet P falls 144 m in 6 seconds. What is the gravitational acceleration of Planet P ? Gravitational accel
Tju [1.3M]

Answer:

The gravitational acceleration of the planet is, g = 8 m/s²

Explanation:

Given data,

The distance the object falls, s = 144 m

The time taken by the object is, t = 6 s

Using the III equations of motion

                  S = ut + ½ gt²

∴                 g = 2S/t²

Substituting the given values,

                   g = 2 x 144 /6²

                      = 8 m/s²

Hence, the gravitational acceleration of the planet is, g = 8 m/s²

7 0
4 years ago
A cycle track is 500 metres long. Amy completes 10 laps. She travelled at an average speed of 12.5 metres per second. She puts o
yanalaym [24]
The fast lap is irrelevant to the question, because it didn't happen
until after the 9 laps that you're interested in.

To be perfectly technical about it, we don't actually have enough
information to answer the question.  You told us her average speed
for 10 laps, but we don't know anything about how her speed may
have changed during the whole 10 laps.  For all we know, maybe
she took a nap first, and then got up and drove 10 laps at the speed
of 125 metres per second.  That would produce the average speed
of 12.5 metres per second and we would never know it  Why not ?
That's only 280 miles per hour.  Bikes can do that, can't they ?

IF we can assume that Amy maintained a totally steady pace through
the entire 10 laps, then we could say that her average for 9 laps was
also 12.5 metres per second.
5 0
3 years ago
What measurements will be made to determine the magnitude of the test-mass centripetal acceleration?
DedPeter [7]

Answer:period, spring constant, radius of circular part, velocity of the test mass, mass of the test-mass, mass of the hanging mass

Explanation:

3 0
4 years ago
Other questions:
  • What is the speed of a proton whose kinetic energy is 3.4 kev ?
    7·1 answer
  • How many protons are in hydrogen -2
    6·1 answer
  • The description for a certain brand of house paint claims a coverage of 475 ft²/gal.
    8·1 answer
  • Convert 2536 mm/min to m/s. Use dimensional analysis.
    14·1 answer
  • 11. A vector M is 15.0 cm long and makes an angle of 20° CCW from x axis and another vector N is 8.0 cm long and makes an angle
    7·1 answer
  • States of matter depend in part on the blank of an item
    9·1 answer
  • When an object is dropped from the top of a tall cliff, your teacher tells you to use -10 m/s2 for the approximate acceleration
    5·2 answers
  • What is 1113.28 in a sig fig?
    6·1 answer
  • The cycling of the air is a natural phenomenon as shown above is the result of
    15·2 answers
  • What was the first major action Roosevelt took AFTER he was inaugurated (sworn in as president)
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!