Answer:
Approximately
. (Assuming that
, and that the tabletop is level.)
Explanation:
Weight of the book:
.
If the tabletop is level, the normal force on the book will be equal (in magnitude) to weight of the book. Hence,
.
As a side note, the
and
on this book are not equal- these two forces are equal in size but point in the opposite directions.
When the book is moving, the friction
on it will be equal to
, the coefficient of kinetic friction, times
, the normal force that's acting on it.
That is:
.
Friction acts in the opposite direction of the object's motion. The friction here should act in the opposite direction of that
applied force. The net force on the book shall be:
.
Apply Newton's Second Law to find the acceleration of this book:
.
ANSWER:
F(h)= 230 N is the horizontal force you will need to move the pickup along the same road at the same speed.
STEP-BY-STEP EXPLANATION:
F(h) is Horizontal Force = 200 N
V is Speed = 2.4 m/s
The total weight increase by 42%
coefficient of rolling friction decrease by 19%
Since the velocity is constant so acceleration is zero; a=0
Now the horizontal force required to move the pickup is equal to the frictional force.
F(h) = F(f)
F(h) = mg* u
m is mass
g is gravitational acceleration = 9.8 m/s^2
200 = mg*u
Since weight increases by 42% and friction coefficient decreases by 19%
New weight = 1+0.42 = 1.42 = (1.42*m*g)
New friction coefficient = μ = 1 - 0.19 = 0.81 = 0.81 u
F(h) = (0.81μ) (1.42 m g)
= (0.81) (1.42) (μ m g)
= (0.81) (1.42) (200)
= 230 N
Explanation :
The heating curve shows how water changes from one state of matter to another based on temperature and the addition or removal of heat over time.
Initially, ice is heated until its temperature reaches
and changes to liquid state.
From the attached graph it is clear that until
the temperature will rise steadily. Here, the liquid begins to vaporize. Vaporization is the state of matter at which liquid state changes to the gaseous state.
So, E is the point which shows the gaseous state.
Answer is B- 200 m
Given:
m (mass of the car) = 2000 Kg
F = -2000 N
u(initial velocity)= 20 m/s.
v(final velocity)= 0.
Now we know that
<u>F= ma</u>
Where F is the force exerted on the object
m is the mass of the object
a is the acceleration of the object
Substituting the given values
-2000 = 2000 × a
a = -1 m/s∧2
Consider the equation
<u>v=u +at</u>
where v is the initial velocity
u is the initial velocity
a is the acceleration
t is the time
0= 20 -t
t=20 secs
s = ut +1/2(at∧2)
where s is the displacement of the object
u is the initial velocity
t is the time
v is the final velocity
a is the acceleration
s= 20 ×20 +(-1×20×20)/2
<u>s= 200 m</u>
Answer:
h f = Wf + K
where the total energy available is h f, Wf is the work function or the work needed to remove the electron and K is the kinetic energy of the removed electron
If K = zero then hf = Wf
Wf = h f = h c / λ or
λ = h c / Wf = 6.63E-34 * 3.0E8 / (3.7 * 1.6E-19)
λ = 6.63 * 3 / (3.7 * 1.6) E-7 = 3.36E-7
This would be 3360 angstroms or 336 millimicrons
Visible light = 400-700 millimicrons