Answer:
a. If an object's speed is constant, then its acceleration must be zero.
FALSE
As we know that acceleration is defined as the rate of change in velocity

so we can not say anything about the acceleration when speed is given to as and no information is given about velocity
b. If an object's acceleration is zero, then its speed must be constant.
TRUE
As we know that acceleration is defined as the rate of change in velocity

Since we know that if acceleration is 0 then velocity must be constant and hence speed is also constant
c. If an object's velocity is constant, then its speed must be constant.
TRUE
Since velocity is constant then it shows that its magnitude and direction both are constant so its speed is also constant.
d. If an object's acceleration is zero, its velocity must be constant.
TRUE
As we know that acceleration is defined as the rate of change in velocity

Since we know that if acceleration is 0 then velocity must be constant
e. If an object's speed is constant, then its velocity must be constant.
FALSE
Speed is just the magnitude so we can not say about its direction and hence if speed is constant then velocity may or may not change
Answer:
Mass = 0.04 Kg
Explanation:
Given the following data;
Density = 800 kg/m³
Volume = 5 * 10^{-5} m³
To find the mass of the object;
Density can be defined as mass all over the volume of an object.
Simply stated, density is mass per unit volume of an object.
Mathematically, density is given by the formula;

Making mass the subject of formula, we have;

Substituting the values into the formula, we have;

Mass = 0.04 Kg
Answer:

Explanation:
First, we calculate the work done by this force after the box traveled 14 m, which is given by:
![W=\int\limits^{x_f}_{x_0} {F(x)} \, dx \\W=\int\limits^{14}_{0} ({18N-0.530\frac{N}{m}x}) \, dx\\W=[(18N)x-(0.530\frac{N}{m})\frac{x^2}{2}]^{14}_{0}\\W=(18N)14m-(0.530\frac{N}{m})\frac{(14m)^2}{2}-(18N)0+(0.530\frac{N}{m})\frac{0^2}{2}\\W=252N\cdot m-52N\cdot m\\W=200N\cdot m](https://tex.z-dn.net/?f=W%3D%5Cint%5Climits%5E%7Bx_f%7D_%7Bx_0%7D%20%7BF%28x%29%7D%20%5C%2C%20dx%20%5C%5CW%3D%5Cint%5Climits%5E%7B14%7D_%7B0%7D%20%28%7B18N-0.530%5Cfrac%7BN%7D%7Bm%7Dx%7D%29%20%5C%2C%20dx%5C%5CW%3D%5B%2818N%29x-%280.530%5Cfrac%7BN%7D%7Bm%7D%29%5Cfrac%7Bx%5E2%7D%7B2%7D%5D%5E%7B14%7D_%7B0%7D%5C%5CW%3D%2818N%2914m-%280.530%5Cfrac%7BN%7D%7Bm%7D%29%5Cfrac%7B%2814m%29%5E2%7D%7B2%7D-%2818N%290%2B%280.530%5Cfrac%7BN%7D%7Bm%7D%29%5Cfrac%7B0%5E2%7D%7B2%7D%5C%5CW%3D252N%5Ccdot%20m-52N%5Ccdot%20m%5C%5CW%3D200N%5Ccdot%20m)
Since we have a frictionless surface, according to the the work–energy principle, the work done by all forces acting on a particle equals the change in the kinetic energy of the particle, that is:

The box is initially at rest, so
. Solving for
:

The blades that spin around in the fan, because they are flat and produce work
Answer:
v1=18.46m/s
v2=29.8cm/s
Explanation:
We know that

the equation of the motion is

we can calculate w by using

Hence, we have that

the speed will be

hope this helps!