Answer:
972 J
Explanation:
At the bottom, all the gravitational potential energy was converted into kinetic energy. If you calculate the GPE, its value will be the same that the KE at the bottom. The GPE can be calculated this way:
GPE = mass×gravity×heigth
GPE = 2.2×9.8×45.08 ≈ 972
Answer:
Time elapsed
Explanation:
Acceleration is a vector quantity. It is defined as:

where
v is the final velocity
u is the initial velocity
t is the time elapsed
Acceleration is measured in meters per second squared (m/s^2). It must be noticed that acceleration is a vector, so it also has a direction. In particular:
- when acceleration is negative, it means that the object is slowing down, so acceleration is in opposite direction to the velocity
- when acceleration is positive, it means that the object is speeding up, so acceleration is in the same direction as the velocity
Answer:
i) 2
ii) No
Explanation:
i) The man will hear two sounds: one through the rail, and one in the air.
ii) The sounds will not reach the man at the same time. Sound travels faster through solids than through gases, so he will hear the sound through the rail before he hears the sound in the air.
Incomplete question.The complete question is here
What is the magnitude of the force needed to hold the outer 2 cm of the blade to the inner portion of the blade? The outer edge of the blade is 21 cm from the center of the blade, and the mass of the outer portion is 7.7 g. Even though the blade is 21cm long, the last 2cm should be treated as if they were at a point 20cm from the center of rotation.
Answer:
F= 0.034 N
Explanation:
Given Data
Outer=2 cm
Edge of blade=21 cm
Mass=7.7 g
Length of blade=21 cm
The last 2cm is treated as if they were at a point 20cm from the center of rotation
To Find
Force=?
Solution
Convert the given frequency to angular frequency
ω = 45 rpm * (2*pi rad / 1 rev) * (1 min / 60 s)
ω= 3/2*π rad/sec
Now to find centripetal force.
F = m×v²/r
F= m×ω²×r
Put the data
F = 0.0077 kg × (3/2×π rad/sec
)²× 0.20 m
F= 0.034 N
The correct answer is option C. i.e. 4%
<span>The total thickness of the stack of sheets is measured to be (0.80 ± 0.02) mm.
The maximum true thickness will be </span>(0.80 + 0.02) mm. = 1.00 mm
Ans, the maximum uncertainity will be <span> (0.20 + 0.02) mm = +/-0.04 mm
Thus, the four sheets true thickness will be </span>1.00 mm +/-0.04 mm
Thus, single sheet thickness will be 0.250 mm +/-0.01 mm
Thus, percentage error = (0.01/0.25) * 100 = 4%