Answer:
16.1 N
Explanation:
From the question,
F = ma.............................. Equation 1
Where F = horizontal force, m = mass of the object, a = acceleration .
Given: m = 7.0 kg, a = 2.3 m/s²
Substitute this values into equation 1
F = (7.0×2.3)
F = 16.1 N.
Hence the magnitude of the horizontal force is 16.1 N
21. light changes its direction when travelling through a new medium because denser mediums have a higher angle of refraction.
Answer:
2.8 m 7.4 m/s
Explanation:
write all the values then use the equations of motion to find the distance and speed. please see attached photo
Answer:

Explanation:
As per mechanical energy conservation we can say that here since friction is present in the barrel so we will have
Work done by friction force = Loss in mechanical energy
so we will have

here we know that



Initial compression in the spring is given as



now from above equation




Answer: To answer this question, we will need the following equation: SPEED = DISTANCE/TIME (A multiplication and division triangle will be shown)i) The speed of the car is calculated by doing 100 metres/ 20 seconds which gives us 5 metres per second. ii) Rearranging the equation earlier, we can make the distance the subject of the equation so that we get SPEED x TIME = DISTANCE. We worked out the speed and the time was given as 1 minute 40 seconds but we cannot plug in the numbers yet as the time has to be converted to units of seconds (because our speed is in meters per second). 1 minute 40 seconds = 60 seconds + 40 seconds = 100 secondsWe then plug in the numbers to get the distance travelled = 5 metres per second x 100 seconds = 500 metres.
Explanation: