Answer:
Explanation:
let force exerted by engine be F.Net force =( F-400)N, applying newton law
F-400 = 1.5 x 10³x18 =27000 ,
F = 27400 N.
velocity after 12 s = 0 + 18 x 12 = 216 m/s
Average velocity = (0 + 216 )/2 = 108 m/s
Average power = force x average velocity = 27400 x 108 = 29.6 10⁵ W .⁶
b) At 12 s , velocity = 216 m/s
Instantaneous power = velocity x force = 216 x 27400 = 59.2 x 10⁶ W.
Answer:
the rocks have the same amount of thermal energy
Tooth fillings are often made of gold or porcelain because these materials are nonreactive.
b. nonreactive.
Answer:
.
Explanation:
By Newton's Second Law, the acceleration 
of an object is proportional to the net force 
on it. In particular, if the mass of the object is 
, then
.
Rewrite this equation to obtain:
.
In this case, the assumption is that the 
force is the only force that is acting on the object. Hence, the net force on the object would also be
Make sure that all values are in their standard units. Forces should be in Newtons (same as 
, and the acceleration of the object should be in meters-per-second-squared (
). Apply the equation to find the mass of the object.
.
