The total work is
(mass of the elevator, kg) x (9.8 m/s²) x (9.0 m) Joules .
Answer:
Force is 57.69 N to the opposite direction of motion of dolphin.
Explanation:
We have force is the product of mass and acceleration.
That is
Force = Mass x Acceleration
F = ma
Mass of dolphin, m = 30 kg
We have equation of motion, v = u + at
Final velocity, v = 7 m/s
Initial velocity, u = 12 m/s
Time, t = 2.60 s
Substituting
7 = 12 + a x 2.6
a = -1.92 m/s²
Force, F = 30 x -1.92 = -57.69 N
So the force is 57.69 N to the opposite direction of motion of dolphin.
The frictional force is always act in opposite direction of motion. if wheels is moving in +x axis or right then the f force is act in -x or left
Answer:
The temperature must the ring be heated so that the sphere can just slip through is 106.165 °C.
Explanation:
For brass:
Radius = 1.3590 cm
Initial temperature = 23.0 °C
The sphere of radius 1.3611 cm must have to slip through the brass. Thus, on heating the brass must have to attain radius of 1.3611 cm
So,
Δ r = 1.3611 cm - 1.3590 cm = 0.0021 cm
<u>The linear thermal expansion coefficient of a metal is the ratio of the change in the length per 1 degree temperature to its length.</u>
<u>Thermal expansion for brass = 19×10⁻⁶ °C⁻¹</u>
Thus,

Also,

So,

Solving for final temperature as:

<u>Final temperature = 106.165 °C</u>