Answer:
38.6 N
2.57 m/s²
Explanation:
Draw a free body diagram of the box. There are four forces:
Weight force mg pulling down,
Normal force N pushing up,
Friction force Nμ pushing left,
and applied force P pulling at an angle 40°.
Sum of forces in the y direction:
∑F = ma
N + P sin 40° − mg = 0
N = mg − P sin 40°
The net force in the x direction is:
∑F = P cos 40° − Nμ
∑F = P cos 40° − (mg − P sin 40°) μ
∑F = P cos 40° − mgμ + Pμ sin 40°
∑F = P (cos 40° + μ sin 40°) − mgμ
Plugging in values:
∑F = (80 N) (cos 40° + 0.23 sin 40°) − (15 kg) (10 m/s²) (0.23)
∑F = 38.6 N
Net force equals mass times acceleration:
∑F = ma
38.6 N = (15 kg) a
a = 2.57 m/s²
Our eyes detect light only within a range of frequencies called visible light.
The sum of the initial and final velocity divided by 2.
Answer:
The final velocity of the car is 36 m/s.
Explanation:
Given;
initial velocity of the car, u = 20 m/s
time of the car acceleration, t = 4 s
acceleration of the car, a = 4 m/s²
the final velocity of the car is calculated as;
v = u + at
where;
v is the final velocity of the car
v = 20 + (4 x 4)
v = 36 m/s
Therefore, the final velocity of the car is 36 m/s.
Answer:
The answer is below
Explanation:
We are to check if the statement is true of false. If it is false, we correct the statement.
Solution:
Acceleration is the time rate of change of velocity. It is the ratio of the change in velocity to the change in time. The acceleration can be gotten from a velocity time graph by finding the slope of the graph.
The x coordinate represent the time and the y coordinate velocity.
5) Graph A passes through the point (0, 0) and (4, 24). Therefore the acceleration (slope) is:
Acceleration = 
This is correct.
6) Graph B is a straight line of 12 m/s. It passes through (0, 12) and (4, 12). Hence:
Acceleration = 
This is false.
Therefore the acceleration of graph B is 0 m/s².
