(a) The kinetic energy of the projectile when it reaches the highest point in its trajectory is 900 J.
(b) The work done in firing the projectile is 2,500 J.
<h3>
Kinetic energy of the projectile at maximum height</h3>
The kinetic energy of the projectile when it reaches the highest point in its trajectory is calculated as follows;
K.E = ¹/₂mv₀ₓ²
where;
- m is mass of the projectile
- v₀ₓ is the initial horizontal component of the velocity at maximum height
<u>Note:</u> At maximum height the final vertical velocity is zero and the final horizontal velocity is equal to the initial horizontal velocity.
K.E = (0.5)(2)(30²)
K.E = 900 J
<h3>Work done in firing the projectile</h3>
Based on the principle of conservation of energy, the work done in firing the projectile is equal to the initial kinetic energy of the projectile.
W = K.E(i) = ¹/₂mv²
where;
- v is the resultant velocity
v = √(30² + 40²)
v = 50 m/s
W = (0.5)(2)(50²)
W = 2,500 J
Thus, the kinetic energy of the projectile when it reaches the highest point in its trajectory is 900 J.
The work done in firing the projectile is 2,500 J.
Learn more about kinetic energy here: brainly.com/question/25959744
#SPJ1
It will cause heat from friction
Answer:
105 mg
Explanation:
Given that:
1 baked potato provides 30 mg of vitamin C.
So,
70 baked potatoes provide 
mg of vitamin C
Also,
70 potatoes = 20 lb
So,
20 lb potatoes provide mg of vitamin C
Thus,
1 lb potatoes provide 
mg of vitamin C
<u>Thus, 105 mg of Vitamin C are provided per pound of the potatoes.</u>
Answer:
If a Gaussian surface is completely inside an electrostatic conductor, the electric field must always be zero at all points on that surface.
Explanation:
Option A is incorrect because, given this case, it is easier to calculate the field.
Option B is incorrect because, in a situation where the surface is placed inside a uniform field, option B is violated
Option C is also incorrect because it is possible to be a field from outside charges, but there will be an absence of net flux through the surface from these.
Hence, option D is the correct answer. "If a Gaussian surface is completely inside an electrostatic conductor, the electric field must always be zero at all points on that surface."
Answer:
v = 4.76 m/s
Explanation:
Given,
The distance traveled by her bike, d = 10 miles
The time of her travel, t = 2.1 m/s
The velocity of an object is defined as the distance traveled by the object to the time of travel. Therefore,
V = d/t m/s
= 10 / 2.1
= 4.76 m/s
Hence, The velocity of her bike is, V = 4.76 m/s
