Answer:
13.33 K
Explanation:
Given that,
Heat absorbed, Q = 30 J
Mass of nail, m = 5 g = 0.005 kg
The specific heat capacity of the nail is 450 J/kg-°C.
We need to find the increase in the temperature during the process. The heat absorbed in a process is as follows:
[tex]Q=mc\Delta T\\\\\Delta T=\dfrac{Q}{mc}\\\\\Delta T=\dfrac{30}{0.005\times 450}\\\\=13.33\ K[/tex]
So, the increase in temperature is 13.33 K.
A Catapult throws a payload in a circle with an arm that is 65.0 cm long. At a certain instant, the arm is rotating at 8.0 rad/s and the angular speed is increasing at 40.0 rad/s2. For this instant, find the magnitude of the acceleration of the payload.
Answer:
The acceleration of the payload is 26 m/s2.
Explanation:
length, L = 65 cm = 0.65 m
angular acceleration = 40 rad/s^2
The acceleration is given by
a = angular acceleration x length
a = 40 x 0.65
a = 26 m/s^2
vector A has a magnitude of 8 unit make an angle of 45° with posetive x axis vector B also has the same magnitude of 8 unit along negative x axis find the magnitude of A+B?
Answer:
45 × 8 units = A + B as formular
Think about a thermos bottle. It consists of an inner bottle with a shiny silver surface separated from an outer container by a space with no air. In what ways does it block conduction, convection, and radiation?
Answer:
Radiation
Explanation:
Conduction, convection and radiation are the three modes of heat transfer.
1. Conduction: When the one end is heated of any rod, the heat transfer to the other end by the vibrational motion of the molecules, it is called conduction.
The heat transfer in a solid is due to the conduction.
2. Convection: When the liquid or gas is heated, the molecules which is in contact to the heat, heated first and due to the decrease in density they moves up and the molecules on the upper side are higher in density so they moves down. These are called convection currents. The process continues till the entire liquid becomes heated. It generally takes place in liquids and gases.
3. Radiation: The process of heat transfer in which no molecules takes place is called radiation. The heat coming from sun is due to the radiation. It does not require any medium.
In the thermos bottle, as there is no air between the two layers, so the heat transfer is due to the radiation.
Topic: Chapter 10: Projectory or trajectile?
Projectile range analysis:
A projectile is launched from the ground at 10 m/s, at
an angle of 15° above the horizontal and lands 5.1 m away.
What other angle could the projectile be launched at, with the same velocity,
and land 5.1 m away?
90°
75°
45
50°
30°
Answer:
The other angle is 75⁰
Explanation:
Given;
velocity of the projectile, v = 10 m/s
range of the projectile, R = 5.1 m
angle of projection, 15⁰
The range of a projectile is given as;
[tex]R = \frac{u^2sin(2\theta)}{g}[/tex]
To find another angle of projection to give the same range;
[tex]5.1 = \frac{10^2 sin(2\theta)}{9.81} \\\\100sin(2\theta) = 50\\\\sin(2\theta) = 0.5\\\\2\theta = sin^{-1}(0.5)\\\\2\theta = 30^0\\\\\theta = 15^0\\\\since \ the \ angle \ occurs \ in \ \ the \ first \ quadrant,\ the \ equivalent \ angle \\ is \ calculated \ as;\\\\90- \theta = 15^0\\\\\theta = 90 - 15^0\\\\\theta = 75^0[/tex]
Check:
sin(2θ) = sin(2 x 75) = sin(150) = 0.5
sin(2θ) = sin(2 x 15) = sin(30) = 0.5
A 0.495-kg hockey puck, moving east with a speed of 4.50 m/s , has a head-on collision with a 0.720-kg puck initially at rest. Assuming a perfectly elastic collision, what will be the speed (magnitude of the velocity) of each object after the collision?
Answer:
a) [tex]v_1=-0.833m/s[/tex]
b) [tex]V_2=12.5m/s[/tex]
Explanation:
From the question we are told that:
Hockey puck Mass [tex]m_1=0.495kg[/tex]
Hockey puck Speed [tex]u_1=4.50m/s[/tex]
Puck Mass [tex]m_2=0.720kg[/tex]
Assuming
Initial speed of Puck [tex]u_2=0[/tex]
Generally the equation for Speed of First Puck is mathematically given by
[tex]v_1=(\frac{m_1-m_2}{m_1+m_2})*v_1+(\frac{2m_2}{m_1+m_2})u_2[/tex]
[tex]v_1=(\frac{0.495-0.720}{0.495+0.720})*4.50+0[/tex]
[tex]v_1=-0.833m/s[/tex]
Generally the equation for Speed of Second Puck is mathematically given by
[tex]V_2=(\frac{2m_1}{m_1+m_2})u_2-(\frac{m_1-m_2}{m_1+m_2})v[/tex]
[tex]V_2=(\frac{2*0.495}{0.495*0.720})*4.50-0[/tex]
[tex]V_2=12.5m/s[/tex]
a certain projetor uses a concave mirror for projecting an object's image on a screen .it produces on image that is 4 times bigger than the object and the screen is 5 m away from the mirror as shown in fig 5.2, calculate the focal length of the mirror.
Answer:
f = 1 m
Explanation:
The magnification of the lens is given by the formula:
[tex]M = \frac{q}{p}[/tex]
where,
M = Magnification = 4
q = image distance = 5 m
p = object distance = ?
Therefore,
[tex]4 = \frac{5\ m}{p}\\\\p = \frac{5\ m}{4}\\\\p = 1.25\ m[/tex]
Now using thin lens formula:
[tex]\frac{1}{f}=\frac{1}{p}+\frac{1}{q}\\\\\frac{1}{f} = \frac{1}{1.25\ m}+\frac{1}{5\ m}\\\\\frac{1}{f} = 1\ m^{-1}\\\\[/tex]
f = 1 m
A closely wound, circular coil with radius 2.70 cm has 800 turns. What must the current in the coil be if the magnetic field at the center of the coil is 0.0750 T
Answer:
Approximately 4.029 A
Explanation:
We can use the formula that the B field of a few loops all with current in same direction is permeability of free space (mu)* current * Number or loops divided by 2*radius. You are given B field, radius(convert into meters), number of loops and mu is 4pi * 10^-7. Solve for current and you get 4.029 Amperes.
the Period T of oscillation of a Single Pendulum depends on the length l, and acceleration g. Determine the exact form of the dependence.
Answer:
[tex]{ \tt{check \: in \: the \: pic}}[/tex]
If an object, initially at rest, accelerates at the rate of 25m/s2, what will the magnitude of the displacement be after 50s
Answer:
31250 meters
Explanation:
Given data
Intitially at rest, the velocity will be
u= 0m/s
acceleration a= 25m/s^2
Time= 50s
We know that the expression for the displacement is given as
S=U+ 1/2at^2
S= 0+ 1/2*25*50^2
S= 12.5*2500
S=31250 meters
Hence the displacement is 31250 meters
how can scientific method solve real world problems examples
A 10-cm-long spring is attached to the ceiling. When a 2.0 kg mass is hung from it, the spring stretches to a length of 15 cm.What is the spring constant k?How long is the spring when a 4.0 kg mass is suspended from it?
As the spring is stretched, it exerts an upward restoring force f. At maximum extension, Newton's second law gives
∑ F = f - mg = 0 ==> f = (2.0 kg) (9.8 m/s²) = 19.6 N
By Hooke's law, if k is the spring constant, then
f = kx ==> k = f/x = (19.6 N) / (0.15 m) ≈ 130 N/m
A 4.0 kg mass would cause the spring to exert a force of
f = (4.0 kg) (9.8 m/s²) = 39.2 N
which would result in the spring stretching a distance x such that
39.2 N = (130 N/m) x ==> x = (39.2 N) / (130 N/m) ≈ 0.30 m ≈ 30 cm
Two positive charges, 91 = 5 x 10-'[C] and q2 =1 x 10-9 [C], are
separated by a distance of d=0.05 m. At location 'P' between the
two charges, the net electric field is found to be zero.
b. [10 points] The distance between charge qı and location 'P' is
considered to be 'x'. Find the value of 'x' in [cm]
Answer:
wareffctgggyyggghhhh
g A computer is reading data from a rotating CD-ROM. At a point that is 0.0189 m from the center of the disk, the centripetal acceleration is 241 m/s2. What is the centripetal acceleration at a point that is 0.0897 m from the center of the disc?
Answer:
the centripetal acceleration at a point that is 0.0897 m from the center of the disc is 1143.8 m/s²
Explanation:
Given the data in the question;
centripetal acceleration a[tex]_c[/tex]₁ = 241 m/s²
radius r₁ = 0.0189 m
radius r₂ = 0.0897 m
centripetal acceleration a[tex]_c[/tex]₂ = ? m/s²
since the rotational period will be the same for the two disk,
we use the centripetal acceleration formula a[tex]_c[/tex] = (4π²r/T²) to find the rotational period for the first disk.
a[tex]_c[/tex]₁ = (4π²r₁/T²)
make T² subject of formula
T² = 4π²r₁ / a[tex]_c[/tex]₁
we substitute
T² = ( 4 × π² × 0.0189 ) / 241
T² = 0.00309602528 s²
Now we use the same formula to find a[tex]_c[/tex]₂
a[tex]_c[/tex]₂ = ( 4π²r₂ / T² )
we substitute
a[tex]_c[/tex]₂ = ( 4 × π² × 0.0897 ) / 0.00309602528
a[tex]_c[/tex]₂ = 1143.8 m/s²
Therefore, the centripetal acceleration at a point that is 0.0897 m from the center of the disc is 1143.8 m/s²
A flat, 75-turn, coil is oriented with its plane perpendicular to a uniform magnetic field that varies steadily from 0.00 To 1.20 T in 20.0 ms. The diameter of each coil is 10 cm. Calculate the emf induced in the coil during this time, in volts.
You are on an airplane that is landing. The plane in front of your plane blows a tire. The pilot of your plane is advised to abort the landing, so he pulls up, moving in a semicircular upward-bending path. The path has a radius of 450 m with a radial acceleration of 17 m/s^2.
Required:
What is the plane's speed?
Answer:
v = 87.46 m/s
Explanation:
The radial acceleration is the centripetal acceleration, whose formula is given as:
[tex]a_c = \frac{v^2}{r}[/tex]
where,
[tex]a_c[/tex] = centripetal acceleration = 17 m/s²
v = planes's speed = ?
r = radius of path = 450 m
Therefore,
[tex]17\ m/s^2 = \frac{v^2}{450\ m}\\\\v^2 = (17\ m/s^2)(450\ m)\\\\v = \sqrt{7650\ m^2/s^2}[/tex]
v = 87.46 m/s
collisions may take place between
Answer:
Collisions may take place between the reactants.
Explanation:
The collision frequency must be greater than the frequency factor for the reaction. A collision between the reactants must occur.
Consider a tall building of height 200.0 m. A stone A is dropped from the top (from the cornice of the building). One second later another stone B is thrown vertically up from the point on the ground just below the point from where stone A is dropped.Birthstones meet at half the height of the tower. (a) Find the initial velocity of vertical throw of stone B.(b) Find the velocities of A and B, just before they meet.
Answer:
a) v₀ = 44.27 m / s, b) stone A v = 44.276 m / s, stone B v = 0.006 m / s
Explanation:
a) This is a kinematics exercise, let's start by finding the time it takes for stone A to reach half the height of the building y = 100 m
y = y₀ + v₀ t - ½ gt²
as the stone is released its initial velocity is zero
y- y₀ = 0 - ½ g t²
t = [tex]\sqrt{ -2(y-y_o)/g}[/tex]
t = [tex]\sqrt{ -2(100-200)/9.8}[/tex]
t = 4.518 s
now we can find the initial velocity of stone B to reach this height at the same time
y = y₀ + v₀ t - ½ g t²
stone B leaves the floor so its initial height is zero
100 = 0 + v₀ 4.518 - ½ 9.8 4.518²
100 = 4.518 v₀ - 100.02
v₀ = [tex]\frac{100-100.02}{4.518}[/tex]
v₀ = 44.27 m / s
b) the speed of the two stones at the meeting point
stone A
v = v₀ - gt
v = 0 - 9.8 4.518
v = 44.276 m / s
stone B
v = v₀ -g t
v = 44.27 - 9.8 4.518
v = 0.006 m / s
why is the water drawn from the bottom of the dam rather than the top?
Answer:
because minerals can be gotten from the bottom
Explanation:
it's self explanatory
PLEASE HELP ME WITH THIS ONE QUESTION
What is the rest energy of a proton? (c = 2.9979 x 10^9 m/s, mp = 1.6726 x 10^-27)
Answer:
multiply mp and c^2
Explanation:
e=mc^2
a vessel with mass 10kg intially moving withthe velocicity 12m s along the x axis explodes into three exactly identical pieces Just after the explosion one piece moves with speed 10 m s along the x axis and asecond piece moves with speed 10 m s along the y axis What iis the magnitude of the component of velocity of the third piece along the y axiss
Answer:
Explanation:
Apply law of conservation of momentum along y-axis.
Initially there was no momentum along y-axis. So there will be nil momentum along y-axis again finally.
Let the mass of each piece after breaking be m .
Momentum of piece moving along positive y-axis
= m x 10 = 10m .
Let the component of velocity of third piece along y-axis be v .
Its momentum along the same direction = m v .
Total momentum along y -axis = 10 m + m v
According to law of conservation of momentum
10 m + mv = 0
v = - 10 m/s .
Component of velocity of the third piece along y-axis will be - 10 m/s .
In other words it will be along negative y-axis with speed of 10 m/s.
3
Select the correct answer.
What is a substance?
Answer:
physical material from which something is made or which has discrete existence
Explanation:
Why are objects measured?
In order to find out how long/wide/heavy/high/dense/deep/ massive/voluminous/reflective/opaque/ tansparent/warm/cold/hard/soft/ malleable/flexible/rigid/radioactive/old/ valuable/symmetrical/flat/regular/ irregular they are.
In a way that you can easily and conveniently describe to other people.
Question 9 of 10
According to the law of conservation of momentum, the total initial
momentum equals the total final momentum in a(n)
A. Interacting system
B. System interacting with one other system
C. Isolated system
D. System of balanced forces
Answer:
The answer is C. Isolated System
Answer:
C. Isolated system
Explanation :
∵According to law of conservation of momentum ,In an isolated system ,the total momentum remains conserved.
3. Calculate the force it would take to accelerate a 50 ka bike at a rate of 3 m/s2 (6 points)
Answer:
150 N
Explanation:
Given that,
Acceleration (a) = 3 m/s²Mass of the bike (m) = 50 kgWe are asked to calculate force required.
[tex]\longrightarrow[/tex] F = ma
[tex]\longrightarrow[/tex] F = (50 × 3) N
[tex]\longrightarrow[/tex] F = 150 N
1. A message signal m(t) has a bandwidth of 5kHz and a peak magnitude of 2V. Estimate the bandwidth of the signal u(t) obtained when m(t) frequency modulates a carrier with a) kf = 10 Hz/V, b) kf = 100 Hz/V, and c) kf = 1000 Hz/V.
Answer:
3v at 5.3 herts
Explanation:
A 55 g soapstone cube--a whisky stone--is used to chill a glass of whisky. Soapstone has a density of 3000 kg/m3, whisky a density of 940 kg/m3. What is the approximate normal force of the bottom of the glass on a single stone?
Answer:
[tex]N=0.37N[/tex]
Explanation:
Mass [tex]m=55g=>0.055kg[/tex]
Soapstone Density [tex]\rho_s=3000kg/m^2[/tex]
Whisky Density [tex]\rho_w=940kg/m^2[/tex]
Generally the equation for Force is mathematically given by
[tex]F=U+N[/tex]
Therefore
[tex]N=m*g-(\frac{m}{\rho_s})*\rho_w*g[/tex]
[tex]N=0.055*9.81 - {(\frac{0.055}{3000})*940*9.81}[/tex]
[tex]N=0.37N[/tex]
A 0.20 mass on a horizontal spring is pulled back a certain distance and released. The maximum speed of the mass is measured to be 0.20 . If, instead, a 0.40 mass were used in this same experiment, choose the correct value for the maximum speed.
a. 0.40 m/s.
b. 0.20 m/s.
c. 0.28 m/s.
d. 0.14 m/s.
e. 0.10 m/s.
Answer:
d
Explanation:
Ya gon find the Kenitic Energy first
K=½mv²===> K=½×0.2×(0.2)²===> 0.1(0.04)===> 0.004
and now the replacement:
0.004=½×0.4V²====> v²=0.02===> V=0.14m/s
A 165-km-long high-voltage transmission line 2.00 cm in diameter carries a steady current of 1,015 A. If the conductor is copper with a free charge density of 8.50 1028 electrons per cubic meter, how many years does it take one electron to travel the full length of the cable?
Answer:
22.1 years
Explanation:
Since the current in the wire is I = nevA where n = electron density = 8.50 × 10²⁸ electrons/cm³ × 10⁶ cm³/m³= 8.50 × 10³⁴ electrons/m³, e = electron charge = 1.602 × 10⁻¹⁹ C, v = drift velocity of electrons and A = cross-sectional area of wire = πd²/4 where d = diameter of wire = 2.00 cm = 2 × 10⁻² m
Making v subject of the formula, we have
v = I/neA
So, v = I/neπd²/4
v = 4I/neπd²
Since I = 1,015 A, substituting the values of the other variables into the equation, we have
v = 4I/neπd²
v = 4(1,015 A)/[8.50 × 10³⁴ electrons/m³ × 1.602 × 10⁻¹⁹ C × π ×(2 × 10⁻² m)²]
v = 4(1,015 A)/[8.50 × 10³⁴ electrons/m³ × 1.602 × 10⁻¹⁹ C × π × 4 × 10⁻⁴ m²]
v = (1,015 A)/[42.779 × 10¹¹ electronsC/m]
v = 23.73 × 10⁻¹¹ m/s
v = 2.373 × 10⁻¹⁰ m/s
Since distance d = speed, v × time, t
d = vt
So, the time it takes one electron to travel the full length of the cable is t = d/v
Since d = distance moved by free charge = length of transmission line = 165 km = 165 × 10³ m and v = drift velocity of charge = 2.373 × 10⁻¹⁰ m/s
t = 165 × 10³ m/2.373 × 10⁻¹⁰ m/s
t = 69.54 × 10⁷ s
t = 6.954 × 10⁸ s
Since we have 365 × 24 hr/day × 60 min/hr × 60 s/min = 31536000 s in a year = 3.1536 × 10⁷ s
So, 6.954 × 10⁸ s = 6.954 × 10⁸ s × 1yr/3.1536 × 10⁷ s = 2.21 × 10 yrs = 22.1 years
It will take one electron 22.1 years to travel the full length of the cable
uppose that 3 J of work is needed to stretch a spring from its natural length of 32 cm to a length of 49 cm. (a) How much work (in J) is needed to stretch the spring from 37 cm to 45 cm
Answer:
0.113 J
Explanation:
Applying,
w = ke²/2................. Equation 1
Where w = workdone in stretching the spring, k = spring constant, e = extension
make k the subject of the equation
k = 2w/e²................ Equation 2
From the question,
Given: w = 3 J, e = 49-32 = 17 cm = 0.17 m
Substitute these values into equation 2
k = (2×3)/0.17²
k = 6/0.17
k = 35.29 N/m
(a) if the spring from 37 cm to 45 cm,
Then,
w = ke²/2
Given: e = 45-37 = 8 cm = 0.08
w = 35.29(0.08²)/2
w = 0.113 J
A proton is released from rest at the positive plate of a parallel-plate capacitor. It crosses the capacitor and reaches the negative plate with a speed of 54000 m/s. The experiment is repeated with a He+ ion (charge e, mass 4 u).What is the ion's speed at the negative plate?
