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
m_a_m_a [10]
3 years ago
13

A 60-kg woman stands on the very end of a uniform board, which is supported one-quarter of the way from one end and is balanced.

What is the mass of the board?
a. 60 kg
b. 30 kg
c. 20 kg
d. 15 kg
e. 120 kg
Physics
1 answer:
Tasya [4]3 years ago
5 0

B 30 kg because


One quarter =1/2
Kg=60

1/2 of Kg
1/2*60
30 kg
You might be interested in
DONT ANSWER WITH A LINK PLEASE I NEED AN ANSWER FROM SOMEONE!
rjkz [21]
At 4 m/s?

How do the two kinetic energies compare to one another? QUADRUPLES !

#3 What is the kinetic energy of a 2,000 kg bus that is moving at 30 m/s?

Potential energy
3 0
3 years ago
Read 2 more answers
The heat capacity of object B is twice that of object A. Initially A is at 300 K and B at 450 K. They are placed in thermal cont
ivann1987 [24]

Answer:

The final temperature of both objects is 400 K

Explanation:

The quantity of heat transferred per unit mass is given by;

Q = cΔT

where;

c is the specific heat capacity

ΔT is the change in temperature

The heat transferred by the  object A per unit mass is given by;

Q(A) = caΔT

where;

ca is the specific heat capacity of object A

The heat transferred by the  object B per unit mass is given by;

Q(B) = cbΔT

where;

cb is the specific heat capacity of object B

The heat lost by object B is equal to heat gained by object A

Q(A) = -Q(B)

But heat capacity of object B is twice that of object A

The final temperature of the two objects is given by

T_2 = \frac{C_aT_a + C_bT_b}{C_a + C_b}

But heat capacity of object B is twice that of object A

T_2 = \frac{C_aT_a + C_bT_b}{C_a + C_b} \\\\T_2 = \frac{C_aT_a + 2C_aT_b}{C_a + 2C_a}\\\\T_2 = \frac{c_a(T_a + 2T_b)}{3C_a} \\\\T_2 = \frac{T_a + 2T_b}{3}\\\\T_2 = \frac{300 + (2*450)}{3}\\\\T_2 = 400 \ K

Therefore, the final temperature of both objects is 400 K.

4 0
3 years ago
A balloon is filled with helium at a pressure of 2.4 x 105 Pa. The balloon is at a
garri49 [273]
1)
p = 2.4 * 10^5 Pa
T = 18° C + 273.15 = 291.15 k
r = 0.25 m => V = [4/3]π(r^3) = [4/3]π(0.25m)^3 = 0.06545 m^3 = 65.45 L

Use ideal gas equation: pV = nRT => n = pV / RT = [2.4*10^5 Pa * 0.06545 m^3] / [8.31 J/k*mol * 291.15k] = 6.492 mol

Avogadro number = 1 mol = 6.022 * 10^23 atoms

Number of atoms = 6.492 mol * 6.022 *10^23 atom/mol = 39.097 * 10^23 atoms = 3.91 * 10^24 atoms

2) Double atoms => double volume

V2 / V1 = r2 ^3 / r1/3

2 = r2 ^3 / r1 ^3 => r2 ^3 = 2* r1 ^3

r2 = [∛2]r1

The factor is ∛2
5 0
3 years ago
Which of the given will facilitate a normal Diels–Alder reaction?
babymother [125]

Answer:

D

Explanation:

-  The rate of the Diels-Alder is orders of magnitude faster if there is an electron-withdrawing group on the dienophile. For example, replacing a hydrogen on ethene with the electron-withdrawing group CN results in about a 10^5 increase in the reaction rate.

- Other common electron withdrawing functional groups that will accelerate the Diels Alder reaction of dienophiles include aldehydes, ketones, and esters.

- In short, any functional group conjugated with the pi bond which can act as a pi acceptor will accelerate a Diels-Alder reaction with a typical diene.

- See attachment for graphical explanation.

7 0
3 years ago
A car has a mass of 550 kg. What is the weight of the car?
lozanna [386]
1212.54 is what 550 kgs is equal to the weight of the car
3 0
3 years ago
Read 2 more answers
Other questions:
  • A car traveling at a constant velocity goes a distance of 198 kilometers in 2.2 hours. What is the velocity of the car?
    7·1 answer
  • Noah drops a rock with a density of 1.73 g/cm3 into a pond. Will the rock float or sink? Explain your answer.
    10·2 answers
  • Which one of the following states of matter has no definite shape but does have a fixed volume A. Liquid B. Element C. Gas D. So
    7·2 answers
  • Anne should use a to transfer electric energy into motion. She should also use a to start and stop the flow of current.
    15·1 answer
  • Which copper wire would have the lowest resistance?
    10·2 answers
  • What tension must a 50.0 cm length of string support in order to whirl an attached 1,000.0 g stone in a circular path at 5.00 m/
    8·1 answer
  • Save
    7·1 answer
  • 2. How does inherent value differ from instrumental value? *
    12·1 answer
  • 17. A ball on the end of a string is
    11·1 answer
  • What is non uniform velocity​
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!