Answer:
the net work is 0
Explanation:
in an isolated system, there is no energy entering or exiting the system, and since work is dependent on the change in energy (W = ΔE) , with no change in energy, there is no work done. the net work done on or by the system must be 0
Answer:
W = 7000 J
Explanation:
To solve this problem we use that the speed of the bicycle is constant, therefore its acceleration is zero
F -fr = 0
F = fr
where F is the force applied by the child
Work is defined by
W = F. x
W = F x cos θ
in this case the child's force is parallel to the movement, therefore the angle is zero and cos 0 = 1
let's calculate
W = 35 200
W = 7000 J
Answer:
baking- is a method of cooking food that uses prolonged dry heat, normally in an oven, but also in hot ashes, or on hot stones. The primary source of heat is radiation. Fans within the oven will increase cooking times via convection of the air.
consider the motion in Y-direction
v₀ = initial velocity = 29 Sin62 = 25.6 m/s
a = acceleration = - 9.8 m/s²
t = time of travel
Y = vertical displacement = - 0.89 m
using the equation
Y = v₀ t + (0.5) a t²
- 0.89 = (25.6) t + (0.5) (- 9.8) t²
t = 5.3 sec
consider the motion along the horizontal direction :
v₀ = initial velocity = 29 Cos62 = 13.6 m/s
a = acceleration = 0 m/s²
t = time of travel = 5.3 sec
X = horizontal displacement =?
using the equation
X = v₀ t + (0.5) a t²
X = (13.6) (5.3) + (0.5) (0) t²
X = 72.1 m
d = distance traveled by the center fielder to catch the ball = 107 - x = 107 - 72.1 = 34.9 m
t = time taken = 5.3 sec
v = speed of center fielder
using the equation
v = d/t
v = 34.9/5.3
v = 6.6 m/s
