All categories

3 years ago

How much work is done in holding a 15 N sack of potatoes while waiting in line at the

Physics

1 answer:

marta [7]3 years ago

4 0

Answer: 2700 Joules

Explanation:

Given variables are:

Workdone (w) = ?

Weight of sack (w) = 15N

Time taken (t) = 3 minutes

The standard unit of time is seconds, so convert 3 minutes to seconds

(If 1 minute = 60 seconds

3 minutes = 3 x 60 = 180 seconds)

Recall that work is done is when force is applied on an object over a distance

i.e Workdone = force x distance.

(However, the force acting on the sack of potatoes is weight)

Hence, workdone = weight x time

w = 15N x 180 seconds

w = 2700 J

thus, 2700 joules of work was done.

You might be interested in

A wheel rotates with a constant angular acceleration of  rad/s2. During a certain time interval its angular displacement is  r

Hatshy [7]

Answer:

The angular velocity at the beginning of the interval is $\pi\sqrt{2}\ rad/s$ .

Explanation:

Given that,

Angular acceleration $\alpha=\pi\ rad/s^2$

Angular displacement $\theta=\pi\ rad$

Angular velocity $\omega =2\pi\ rad/s$

We need to calculate the angular velocity at the beginning

Using formula of angular velocity

$\alpha =\dfrac{\omega^2-\omega_{0}^2}{2\theta}$

$\omega_{0}^2=\omega^2-2\alpha\theta$

Where, $\alpha$ = angular acceleration

$\omega$ = angular velocity

Put the value into the formula

$\omega_{0}^2=(2\pi)^2-2\times\pi\times\pi$

$\omega=\sqrt{2\pi^2}$

$\omega_{0}=\pi\sqrt{2}\ rad/s$

Hence, The angular velocity at the beginning of the interval is $\pi\sqrt{2}\ rad/s$ .

3 0

3 years ago

The volume of the moon is about 33% of the volume of the earth.true or false

stealth61 [152]

The moons volume is that of 2 percent of the earth.

4 0

2 years ago

Read 2 more answers

g A 1.45-kg block is pushed against a vertical wall by means of a spring (k = 860 N/m). The coefficient of static friction betwe

olga_2 [115]

Answer:

The minimum compression is $x= 0.046m$

Explanation:

From the question we are told that

The mass of the block is $m_b = 1.45 kg$

The spring constant is $k = 860 N/m$

The coefficient of static friction is $\mu = 0.36$

For the the block not slip it mean the sum of forces acting on the horizontal axis is equal to the forces acting on the vertical axis

Now the force acting on the vertical axis is the force due to gravity which is mathematically given as

$F_y = m_b*g$

And the force acting on the horizontal axis is force due to the spring which is mathematically represented as

$F_x = k *x * \mu$

where x is the minimum compression to keep the block from slipping

Now equating this two formulas and making x the subject

$x = \frac{m_b * g}{k * \mu}$

substituting values we have

$x = \frac{1.45 * 9.8}{860 *0.36}$

$x= 0.046m$

3 0

3 years ago

A book sits on a bookshelf without moving until a student picks it up. Which law best explains why the book remains at rest unti

svetoff [14.1K]

Answer:

Newtons first law

Explanation:

object in rest stays at rest

object in motion stays in motion

8 0

3 years ago

Name two ways to reduce friction and two ways to increase it.

Maurinko [17]

Ways to increase friction

- increase the roughness of the contact materials 
- increase the pressure on the contact 

Ways to decrease friction 

- float the moving body on air 
- suck out any air

4 0

2 years ago