The correct answer is “C” ultrasound. Hope this helps!
Answer:
66.5N
Explanation:
F = kx
Where F = force
K = spring constant
x = compression
Given
K = 950N/m
x = 7.0cm
F = ?
First convert the compression to meters .
7.0cm = 7.0 x 0.01
= 0.07 meters
Therefore
F = 950 x 0.07
= 66.5N
Answer:
When the velocity doesn't change its direction
Explanation:
Since velocity vector has 2 components: direction and magnitude, and speed is the velocity's magnitude. So if the velocity doesn't change its direction, we essentially use its magnitude, aka speed, to calculate the rate of change for acceleration.
Resistance reduces the current. If there is more resistance, there is less current.
Answer:
Minimum work = 5060 J
Explanation:
Given:
Mass of the bucket (m) = 20.0 kg
Initial speed of the bucket (u) = 0 m/s
Final speed of the bucket (v) = 4.0 m/s
Displacement of the bucket (h) = 25.0 m
Let 'W' be the work done by the worker in lifting the bucket.
So, we know from work-energy theorem that, work done by a force is equal to the change in the mechanical energy of the system.
Change in mechanical energy is equal to the sum of change in potential energy and kinetic energy. Therefore,
Therefore, the work done by the worker in lifting the bucket is given as:
Now, plug in the values given and solve for 'W'. This gives,
Therefore, the minimum work that the worker did in lifting the bucket is 5060 J.