Answer:
it means the velocity is changing.
the rate of change of velocity is acceleration
so it means the body is accelerated at 2m/s^2
Answer:
Approximately 21 km.
Explanation:
Refer to the not-to-scale diagram attached. The circle is the cross-section of the sphere that goes through the center C. Draw a line that connects the top of the building (point B) and the camera on the robot (point D.) Consider: at how many points might the line intersects the outer rim of this circle? There are three possible cases:
- No intersection: There's nothing that blocks the camera's view of the top of the building.
- Two intersections: The planet blocks the camera's view of the top of the building.
- One intersection: The point at which the top of the building appears or disappears.
There's only one such line that goes through the top of the building and intersects the outer rim of the circle only once. That line is a tangent to this circle. In other words, it is perpendicular to the radius of the circle at the point A where it touches the circle.
The camera needs to be on this tangent line when the building starts to disappear. To find the length of the arc that the robot has travelled, start by finding the angle which corresponds to this minor arc.
This angle comes can be split into two parts:
.
Also,
.
The radius of this circle is:
.
The lengths of segment DC, AC, BC can all be found:
In the two right triangles and , the value of and can be found using the inverse cosine function:
.
The length of the minor arc will be:
.
Answer
given,
mass of block (m₁)= 8 kg
mass of other block (m₂) = 5.75
velocity of first object (v₁) = 5.5 m/s
velocity of second object (v₂) = 6 m/s
a) total momentum before collision = total momentum after collision
m₂v₂ - m₁ v₁ = (m₁ + m₂) V
5.75 x 6 - 8 x 5.5 = (5.75 + 8 ) V
V = - 0.69 m/s
b) negative sign shows the direction motion of object after collision toward left.
c) Initial kinetic energy
K_i = 224.5 J
final kinetic energy
=
=
K_f = 3.23 J
loss in mechanical energy
Δ KE = 3.23 - 224.5
Δ KE = -218.1 J
negative sign shows loss of mechanical energy.
Answer:
400 N
Explanation:
Since the steel bar is uniform, its center of mass must be at its geometric center as well, which is at the same spot as the 75kg mass hanging. So the total mass is 75 + 5 = 80 kg.
Suppose g = 10m/s2, we can then calculate the weight of the system:
W = Fg = 80 * 10 = 800 N
As the weight is at the center with 2 ropes supporting on 2 ends, weight should be evenly distributed on each rope. So each rope is subjected to a tension force of
T = 800 / 2 = 400 N