Answer:
acceleration = -0.042 m/s²
velocity at beginning = 14.167 m/s
velocity at end = 5.7183 m/s
Explanation:
given data
distance d1 = 1 km
distance d2 = 2 km
time t1 = 80 s
time t2 = 120 s + 80s = 200 s
to find out
acceleration and velocity at beginning and end
solution
we apply here law of motion that is
d = vt + 1/2×at²
put value
1000 = v(80) + 1/2×a(80)² ........................1
and
2000 = v(200) + 1/2×a(200)² ........................2
so from equation 1 and 2 we get a and v
a = -0.042 m/s² and
v = 14.167 m/s
so by kinematic final velocity will be
V² = v² + 2ad
V² = (14.167)² + 2×(-0.042)×(2000)
V² = 32.70
V = 5.7183 m/s
so
acceleration = -0.042 m/s²
velocity at beginning = 14.167 m/s
velocity at end = 5.7183 m/s
Answer:
The comparison of unknown quantity with known quantity is called measurement.
Applicable linear expansion equation:
ΔL = αΔTL
In which
ΔL = change in length, α = Linear expansion coefficient of steel, ΔT = change in temperature, L = original length
Therefore,
ΔL = 12*10^-6*(18.5-(-3))*1410 = 0.36378 m
Answer:
The speed will be "18km/s". A further explanation is given below.
Explanation:
According to the question, the values are:
Wavelength,



As we know,
⇒ 
On substituting the values, we get
⇒ 
⇒ 
⇒ 
⇒ 
or,
⇒ 
There are some missing data in the text of the problem. I've found them online:
a) coefficient of friction dry steel piston - steel cilinder: 0.3
b) coefficient of friction with oil in between the surfaces: 0.03
Solution:
a) The force F applied by the person (300 N) must be at least equal to the frictional force, given by:

where

is the coefficient of friction, while N is the normal force. So we have:

since we know that F=300 N and

, we can find N, the magnitude of the normal force:

b) The problem is identical to that of the first part; however, this time the coefficienct of friction is

due to the presence of the oil. Therefore, we have: