Answer:
4.4 seconds
Explanation:
Given:
a = -5.5 m/s²
v₀ = 0 m/s
y₀ = 53 m
y = 0 m
Find: t
y = y₀ + v₀ t + ½ at²
0 = 53 + 0 + ½ (-5.5) t²
0 = 53 − 2.75 t²
t = 4.39
Rounded to two significant figures, it takes 4.4 seconds for the object to land.
Answer:
2. ( b ) zero
3. ( c ) 10 s
4. Uniform then decreasing
Explanation:
2.
Since the motion is uniform, initial and final velocity will be 0, hence acceleration will be zero.
3.
Initial velocity ( u ) = 5 m/s
Final velocity ( v ) = 35 m/s
Acceleration ( a ) 3 m/s^2
To find : Time ( t )
Formula : -
t = v - u / a
= 35 - 5 / 3
= 30 / 3
t = 10 s
Answer:
Toasting in a toaster is usually considered by (infra red) radiation. But the hot coils touch the toast so an element of heating by conduction occurs as well.
Explanation:
We are given that a 500 kg object is hanging from a spring. To determine the amount the spring is stretched we will use Hook's law, which states the following:
Where:
Since the object is hanging the only force acting on the spring is the weight of the object. The weight of the object is:
Where:
Plugging in the values we get:
Solving the operations:
Now we solve for "x" from Hook's law by dividing both sides by "k":
Now we plug in the known values:
Solving the operations:
Therefore, the spring is stretched by 5.4 meters.
The y-axis of the speed-time graph is the speed while the x-axis is the time of travel. In this case, the slope is equal to the change in y over change in x. Change in y is velocity difference while change in x is time difference. Since v<span>elocity difference/ t</span><span>ime difference is the slope, the answer is acceleration. </span>
