Answer:
t = 5.1[s]
Explanation:
To solve this problem we must first use the following equation of kinematics.
[tex]v_{f}=v_{o} -g*t[/tex]
where:
Vf = final velocity = 0
Vo = initial velocity = 25 [m/s]
g = gravity acceleration = 9.81 [m/s²]
t = time [s]
Now replacing:
[tex]0 = 25-9.81*t\\t=25/9.81\\t=2.54[s][/tex]
Note: The key to understand this problem is that when the tennis ball is in the highest position its velocity is zero.
So it will take the same time from the highest point to the ground
t = 2.54 +2.54
t = 5.09 [s]
An airplane accelerates from a speed of 88m/s to a speed of 132 m/s during a 15 second time interval. How far did the airplane travel during the time interval?
Answer:
[tex]1650\:\mathrm{m}[/tex]
Explanation:
We can use the following kinematics equations to solve this problem:
[tex]v_f=v_i+at,\\{v_f}^2={v_i}^2+2a\Delta x[/tex].
Using the first one to solve for acceleration:
[tex]132=88+a(15),\\15a=44,\\a=\frac{44}{15}=2.9\bar{3}\:\mathrm{m/s^2}[/tex].
Now we can use the second equation to solve for the distance travelled by the airplane:
[tex]132^2=88^2+2\cdot2.9\bar{3}\cdot \Delta x,\\\Delta x= \frac{9680}{2\cdot2.9\bar{3}},\\\Delta x =\fbox{$ 1650\:\mathrm{m}$}[/tex](three significant figures).
What is happening to the average kinetic energy of the molecules in a pot of water when it is heated on a stove? Explain your answer.
Answer:
Explanation:
The average kinetic energy of molecules in a pot increases when it is heated on a stove . The heat energy is spent to decrease the intermolecular attractive force . The result is increase in kinetic energy due to increase in the velocity of molecules
formula for kinetic energy of one mole of a monoatomic gas
= 3/2 RT
when temperature increases , kinetic energy increases .
A rectangle box was measured with a length of 4cm, width 2cm, and height 2cm. What is the volume of the box?
Answer:
volume is 64
Explanation:
2×2×4×4
=64
Answer:
[tex]V = 16\ cm^3[/tex]
Explanation:
The Volume of a Rectangular Prism
A rectangular prism is also called a rectangular box and has three dimensions all perpendicular to each other.
Given a rectangular prism of length L, width W, and height H, the volume is calculated as:
V = WLH
We are given the dimensions of a rectangular box: L= 4 cm, W = 2 cm, H = 2 cm. Computing the volume:
V = 2 cm * 4 cm * 2 cm
[tex]\mathbf{V = 16\ cm^3}[/tex]
Help!! ASAP plz
Determine the mass of the object below to the correct degree of precision.
358.3g
358.20g
358.30g
358.2g
Please help me
27. A 20 kg object is at rest. A 6 N force pulls to the right on
the object for 10 seconds.
A) Find the impulse on the object.
B) Find the final momentum of the object.
C) What is its final velocity?
Answer:
a. 60 N*s
b. 60 (kg*m)/s
c. 3 m/s
Explanation:
Givens:
m = 20 kg
v_i = 0 m/s
t = 10 s
F = 6 N
a) Impulse:
I = F*t
I = 6 N*10 s
I = 60 N*s
b) Momentum:
p = v*m
F = m(a)
a = F/m
a = 6 N/20 kg
a = 0.3m/s^2
a = (v_f -v_i)/t
v_f = (0.3 m/s^2)*10 s
v_f = 3.0 m/s
p = 3 m/s*20 kg
p = 60 (kg*m)/s
c. Final velocity
a = (v_f -v_i)/t
v_f = (0.3 m/s^2)*10 s
v_f = 3.0 m/s
The impulse, momentum and final velocity can all be obtained from Newton's second law.
Let us recall that the impulse is obtained as the product of force and time.
Impulse = Force × time
Impulse = 6 N × 10 s = 60 Ns
From Newton's second law of motion;
F.t = mv - mu
Since the object was initially at rest;
F.t = mv
Hence, the final velocity of the object is 60 Kgms-1
The final velocity is obtained from;
F.t = mv
v = F.t/m
v = 6 × 10/20
v = 3 m/s
Learn more about impulse and momentum: https://brainly.com/question/904448
A negative charge of -0.00067 C and a positive charge of 0.00096 C are separated by 0.7 m. What is the force between the two charges?
Answer:
-11,813.87N
Explanation:
According to coulombs law, the Force between the two charges is expressed as;
F = kq1q2/d²
k is the coulombs constant = 9*10⁹kg⋅m³⋅s⁻²⋅C⁻².
q1 = -0.00067 C
q2 = 0.00096 C
d = 0.7m
Substitute into the formula:
F = 9*10^9 * -0.00067 * 0.00096/0.7²
F = 9*10⁹*-6.7*10⁻⁴*9.6*10⁻⁴/0.49
F = -578.88*10⁹⁻⁸/0.49
F = -578.88*10/0.49
F = -5788.8/0.49
F = -11,813.87N
Hence the force between the two charges is -11,813.87N
I’m NC the wind is blowing from the north. If the wind changes direction and begins to blow from the south, what will most likely result.
NC means North Carolina.
Answer:
The temperatures will increase.
Explanation:
What will happen is that the temperature will increase. This is because, in wind direction and weather forecasting, a wind that shifts from the south means that warmer air/temperatures are approaching whereas a wind shift from the north implies that cooler air/temperatures are approaching.
Which one doesn't belong in the group? oxygen, sulfur, selenium,
tellurium *
Your answer
This is a required question
borons
A force of 49 Newtons is applied to a rock, which causes it to be lifted 2 meters in 5 seconds. How much power is exerted during this time?
Select one:
9.8 W
19.6 W
56.4 W
98 W
Answer: 19.6 watts
=================================================
Explanation:
power = (change in work)/(change in time)
p = w/t
work = force*displacement
w = f*d
So we can say:
p = (f*d)/t
We know the following
f = 49 = applied forced = 2 = displacementt = 5 = change in timeLeading to...
p = (f*d)/t
p = (49*2)/5
p = 98/5
p = 19.6 watts
Side note: 1 watt is equal to 1 joule per second