I think the answer would be 70
Answer:
(a)
(b) It won't hit
(c) 110 m
Explanation:
(a) the car velocity is the initial velocity (at rest so 0) plus product of acceleration and time t1
(b) The velocity of the car before the driver begins braking is
The driver brakes hard and come to rest for t2 = 5s. This means the deceleration of the driver during braking process is
We can use the following equation of motion to calculate how far the car has travel since braking to stop
Also the distance from start to where the driver starts braking is
So the total distance from rest to stop is 352 + 88 = 440 m < 550 m so the car won't hit the limb
(c) The distance from the limb to where the car stops is 550 - 440 = 110 m
Explanation:
Given that,
A girl pushes her little brother on his sled with a force of 200. N for 850. m
We need to find the work done by the force of friction acting on the sled. The force of friction is 200 N
Net force = 200 N - 200 N = 0
Work done = 0
If force of friction is 300 N.
Net force = 300 N - 200 N = 100 N
The work done by a force is given by :
W = Fd
Put values,
W = 100 × 850
W = 85000 J
Hence, this is the required solution.
Answer:
The correct answer is
b. Feeding yourself with a spoon
Explanation:
There are two categories of motor skills, fine motor skills and gross motor skills
Fine motorskills also known as dexterity is the synchronized use of small muscles like muscles in the wrists, hands and fingers along with the eyes. Fine motor skills are used for tasks like turning pages or using the computer key board that requires coordinated and precise movements. Human dexterity is reflected in the level of complexity of functions controlled by the nervous system.
Example of fine motor skill is Feeding yourself with a spoon while gross motor skill includes climbing to the top of a large hill spoon, running in a race and crawling
