All categories

3 years ago

If 143 joules of work are needed to move a box 9 meters, what force was used?

Physics

2 answers:

zhuklara [117]3 years ago

8 0

Answer: 16 N

Explanation: Work is expressed in this formula:

W=F x d

Derive for F:

F= W /d

= 143 J / 9 m

= 16 N

brilliants [131]3 years ago

7 0

Your gonna have to divide 143 into 9 and then that will be your answer

You might be interested in

Light is shining perpendicularly on the surface of the earth with an intensity of 680 W/m^2. Assuming that all the photons in th

andrew11 [14]

Answer:

3.066×10^21 photons/(s.m^2)

Explanation:

The power per area is:

Power/A = (# of photons /t /A)×(energy / photon)

E/photons = h×c/(λ)

photons /t /A = (Power/A)×λ /(h×c)

photons /t /A = (P/A)×λ/(hc)

photons /t /A = (680)×(678×10^-9)/(6.63×10^-34)×(3×10^-8)

= 3.066×10^21

Therefore, the number of photons per second per square meter 3.066×10^21 photons/(s.m^2).

4 0

3 years ago

A girl stands on the edge of a merry-go-round of radius 1.71 m. If the merry go round uniformly accerlerates from rest to 20 rpm

Mashutka [201]

Answer:

$a = 0.53 m/s^2$

Explanation:

initially the merry go round is at rest

after 6.73 s the merry go round will accelerates to 20 rpm

so final angular speed is given as

$\omega = 2\pi f$

$\omega = 2\pi ( \frac{20}{60})$

$\omega = 2.10 rad/s$

so final tangential speed is given as

$v = r\omega$

$v = 1.71 (2.10) = 3.58 m/s$

now average acceleration of the girl is given as

$a = \frac{v_f - v_i}{\Delta t}$

$a = \frac{3.58 - 0}{6.73}$

$a = 0.53 m/s^2$

8 0

3 years ago

Explain why squeezing a plastic mustard bottle forces mustard out to top.

Oliga [24]

Answer:

because when squeezing you are increasing pressure within the bottle and there is less pressure on the outside

5 0

3 years ago

Read 2 more answers

A ranger in a national park is driving at 56 km/h when a deer jumps onto the road 65 m ahead of the vehicle. After a reaction ti

vagabundo [1.1K]

Answer:

t = 1.58 s

Explanation:

given,

Speed of ranger, v = 56 km/h

v = 56 x 0.278 = 15.57 m/s

distance, d = 65 m

deceleration,a = 3 m/s²

reaction time = ?

using stopping distance formula

$d = v. t + \dfrac{v^2}{2a}$

$t = \dfrac{d}{v} -\dfrac{v}{2a}$

t is the reaction time

$t = \dfrac{65}{15.57} -\dfrac{15.57}{2\times 3}$

t = 1.58 s

hence, the reaction time of the ranger is equal to 1.58 s.

3 0

3 years ago

For states with larger values of n that admit a d subshell, the d subshell is at even higher energy than the p subshell. In fact

frosja888 [35]

Answer:

Explanation:

Correct order of energy of energy states within an atom is as follows

1s , 2 s, 2 p 3 s ,3 p, 4s , 3d, 4p, 4p,5s etc.

There is discrepancies in this order due to overlapping of outer orbitals with inner orbitals so sometimes outer orbitals have lower energy.

4 0

3 years ago