Here's what you need to memorize for your exam tomorrow.
Distance = (speed) x (time) .
That's it. Memorize it.
-- If the question wants you to find speed, use it exactly in that form.
-- If the question wants you to find speed, then divide each side by (time)
and it says
. Time = (distance) / (speed) .
-- If the question wants you to find time, then divide each side by speed,
and it says
. Time = (distance) / (speed) .
So if you memorize that one equation ... Distance = (speed) x (time) ...
you can solve ANY problem to find distance, speed, or time.
On the sheet in the picture . . . . .
#2). The question is "How long ?". That's TIME that you have to find.
Use the equation in the form of
. TIME = (distance) / (speed)
. = (60 km) / (48 km/h)
. = 1.25 hours .
#3). This one wants you to find SPEED. Use the equation in the form of
. SPEED = (distance) / (time)
but be careful. The time has to be in hours. 55 minutes = 55/60 of an hour.
. SPEED = (distance) / (time)
. = (60 km) / (55/60 hour)
. = (60 x 60 km) / (55 hour)
. = 65.45 km/hr .
#4). This one wants you to find TIME. (It says "How long ?".)
It's two trips, so you have to find the time for each trip.
First trip: TIME = (distance)/(speed) = (24 km)/(65 km/hr) = 0.369 hr
Second trip: TIME = (distance)/(speed) = (50 km)/(80 km/hr) = 0.625 hr
Total time for both trips = (0.369 hr) + (0.625 hr) = 0.994 hour
Answer:
v = 22.54 mph.
Explanation:
Given that,
Distance moved, d = 200 m
Time, t = 19.8 s
We need to find the runner's average speed.
We know that,
1 mile = 1609.34 m
200 m = 0.124 miles
19.8 seconds = 0.0055 h
So,
Speed = distance/time
So, the runner's average speed is 22.54 mph.
Answer:
the resulting angular acceleration is 15.65 rad/s²
Explanation:
Given the data in the question;
force generated in the patellar tendon F = 400 N
patellar tendon attaches to the tibia at a 20° angle 3 cm( 0.03 m ) from the axis of rotation at the knee.
so Torque produced by the knee will be;
T = F × d⊥
T = 400 N × 0.03 m × sin( 20° )
T = 400 N × 0.03 m × 0.342
T = 4.104 N.m
Now, we determine the moment of inertia of the knee
I = mk²
given that; the lower leg and foot have a combined mass of 4.2kg and a given radius of gyration of 25 cm ( 0.25 m )
we substitute
I = 4.2 kg × ( 0.25 m )²
I = 4.2 kg × 0.0626 m²
I = 0.2625 kg.m²
So from the relation of Moment of inertia, Torque and angular acceleration;
T = I∝
we make angular acceleration ∝, subject of the formula
∝ = T / I
we substitute
∝ = 4.104 / 0.2625
∝ = 15.65 rad/s²
Therefore, the resulting angular acceleration is 15.65 rad/s²
It is A. a refrigerator cause a alternating current is current that doesn't stop and the refrigerator is plug into the wall.
