Which kind of energy does the soccer player transfer to the ball?

Which is not expecting acceleration?

Elena L [17]

#1

A point on the outside of a spinning top whose rotational speed is constant.

Since the point at the top is at rest so it will not accelerate at all

A skydiver whose air resistance is equal to that of her weight.

Since weight is counter balanced by air resistance so net force on it is zero so acceleration will be zero

A car on the freeway experiencing a net force of -120 N.

Since net force is not zero so it will accelerate here

A submerged beach ball whose buoyant force is eight times the force of gravity on it.

Since buoyant force is more than the weight so it will not at rest and move upwards with some acceleration

#2

A frictionless spinning merry go round.

Since spinning wheel accelerating due to centripetal force so it is non inertial frame

A falling rock.

Falling rock is accelerating due to gravity so it is again non inertial frame

A hot air balloon moving at 30 degrees east of north with no net force.

since hot air balloon is having no force on it so its acceleration is zero and its an inertial frame

A space shuttle whose boosters just ignited for takeoff.

Since space shuttle is accelerating due to boosters so it is non inertial frame

#3

Here net force on it is due to two given forces

$F_1 = 4320 N$ towards right

$F_2 = 4380 N$ towards left

so here net force is given as

$F = F_2 - F_1$

$F = 4380 - 4320 = 60 N$

since force towards left is more so the direction will be towards left

so correct answer is 60 N towards left

4 0

3 years ago

hhTwo cups of the same size are filled to the brim with clear liquids. Cup A holds water. Cup B contains alcohol. Your teacher c

Taya2010 [7]

You used density, because water/ice has a density of 1, and ice will sink in anything with a lesser density

4 0

3 years ago

Read 2 more answers

The world record for the 100.0 meter dash is 9.580 seconds. Find the speed of the runner in miles per hour.

grigory [225]

Answer:

233.1 miles per hours

Explanation:

Speed: This is defined as the ratio of distance to time. The S.I unit of speed is m/s. speed is a vector quantity because it can only be represented by magnitude only. Mathematically, speed can be expressed as,

S = d/t ....................... Equation 1

Where S = speed of the runner, d = distance covered, t = time.

Given: d = 100 meter , t = 9.580 seconds

Conversion:

If, 1 meter = 0.00062 miles

Then, 100 meters = (0.00062×100) miles = 0.62 miles.

Also

If, 3600 s = 1 h

Then, 9.580 s = (1×9.580)/3600 = 0.00266 hours.

Substitute into equation 1

S = 0.62/0.00266

S = 233.1 miles per hours.

Hence the runner speed is 233.1 miles per hours

7 0

3 years ago

A machine

In-s [12.5K]

Answer:

Power_input = 85.71 [W]

Explanation:

To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.

$W = F*d$

where:

W = work [J] (units of Joules)

F = force [N] (units of Newton)

d = distance [m]

We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.

Now replacing:

$W = (80*10)*3\\W = 2400 [J]$

Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.

$P=\frac{W}{t}$

where:

P = power [W] (units of watts)

W = work [J]

t = time = 40 [s]

$P = 2400/40\\P = 60 [W]$

The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.

$Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}=60/0.7\\P_{introduced}=85.71[W]$

3 0

3 years ago

Which of the following represents an upright image? <br> A. -do<br> B. +m<br> C. -m<br> D. +do

Tom [10]

Answer:

B. +m

Explanation:

The magnification of an image is defined as the ratio between the size of the image and of the object:

$m = \frac{y'}{y}$

where we have

y' = size of the image

y = size of the object

There are two possible situations:

- When m is positive, y' has same sign as y: this means that the image image is upright

- When m is negative, y' has opposite sign to y: this means that the image is upside down

Therefore, the correct option representing an upright image is

B. +m

5 0

2 years ago