Answer:
0.932 m/h
Explanation:
Parameters given:
Distance walked by couple, D = 1.5 km
Time spent in walking, t = 60 min
To solve this we simply apply the formula for average peed:
Average Speed = total distance / total time taken
The question asks specifically to put the answer in miles per hour (m/h), hence, we need to convert the distance to miles and the time to hours:
Distance in miles:
1 km = 0.622 miles
1.5 km = 1.5 * 0.622 = 0.932 miles
Time in hours = 60 / 60 = 1 hour
Hence, the speed is:
Speed = 0.932 / 1 = 0.932 m/h
The average speed of the couple is 0.932 m/h
Answer:
The velocity just before hitting the ground is 
Explanation:
From the question we are told that
The initial speed is 
The final speed is 
From the equations of motion we have that

Where s is the distance travelled which is the height of the cliff
So making it the subject of the the formula we have that

Where a is the acceleration due to gravity with a value 
So


Now we are told that was through horizontally with a speed of

Which implies that this would be its velocity horizontally through out the motion
Now it final velocity vertically can be mathematically evaluated as

Substituting values


The resultant final velocity is mathematically evaluated as

Substituting values


Answer:
To correct the defects of vision by measuring the radius of curvature and thus the power of the lenses.
Explanation:
A spherometer is an instrument used to measure the curvature of objects such as lenses and curved mirrors.
Generally it consists of a fine screw which is moving in a nut carried on the center of a 3 small legged table or frame. The feet forms the vertices of an equilateral triangle. The lower end of the screw and those of the table legs are finely tapered and terminate in hemispheres.
If the screw has two turns of the thread to the milli meter the head is generally divided into 50 equal parts, so that differences of 0.01 millimeter may be measured without using a vernier scale.
The spherometer is used to measure the radius of curvature of the lenses so that the opthalmologist find the focal length of the lens and then give the power to the lens to correct the defects of vision.
Answer: (E) Momentum and mechanical energy
Explanation:
The momentum and the mechanical energy is basically conserved during the given interaction process as the forces on the given system are in the form of internal nature and then the momentum are get conserved.
According to the given question, on the smooth floor when an object are slides by using the spring then the momentum and the mechanical energy are conserved.
The mechanical energy is the combination of both the kinetic and the potential energy that is used for doing some amount of work. Therefore, Option (E) is correct answer.
Explanation:
50 m/s may squared siya sa dun sa may s