Answer:
<h2>42 N</h2>
Explanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question
mass = 7 kg
acceleration = 6 m/s²
We have
force = 7 × 6 = 42
We have the final answer as
<h3>42 N</h3>
Hope this helps you
Answer:
Cost of 1000 kilowatt hour = 6000 cents
Explanation:
Given that
Electricity cost is 6 cents per kilowatt hour.
And we have to found out the cost for one megawatt hour
We know that
1 kilowatt = 1000 watt
1 megawatt = = 1000000 watt
1 megawatt = 1000 kilowatt
1 megawatt hour = 1000 kilowatt hour
Given that cost of 1 kilowatt hour = 6 cents
So the cost of 1000 kilowatt hour = 6 x 1000 cents
Cost of 1000 kilowatt hour = 6000 cents
The work done occurs only in the direction the block was moved - horizontally. Work is given by:
W = F(h) * d
Where F(h) is the force applied in that direction (horizontal) and d is the distance in that direction. In this case, F(h) is the horizontal component of the applied force, F(app). However, the question doesn't give us F(app), so we need to find it some other way.
Since the block is moving at a constant speed, we know the horizontal forces must be balanced so that the net force is 0. This means that F(h) must be exactly balanced by the friction force, f. We can express F(h) as a function of F(app):
F(h) = F(app)cos(23)
Friction is a little trickier - since the block is being PUSHED into the ground a bit by the vertical component of the applied force, F(v), the normal force, N, is actually a bit more than mg:
N = mg + F(v) = mg + F(app)sin(23)
Now we can get down to business and solve for F(app) - as mentioned above:
F(h) = f
F(h) = uN
F(h) = u * (mg + F(v))
F(app)cos(23) = 0.20 * (33 * 9.8 + F(app)sin(23))
F(app) = 76.8
Now that we have F(app), we can find the exact value of F(h):
F(h) = F(app)cos(23)
F(h) = 76.8cos(23)
F(h) = 70.7
And now that we have F(h), we can find W:
W = F(h) * d
W = 70.7 * 6.1
W = 431.3
Therefore, the work done by the worker's force is 431.3 J. This also represents the increase in thermal energy of the block-floor system.
Hello,
<span>A car with a mass of 2.0×10^3 kg is traveling at 15m/s. We need to find the momentum of the car. To do so, follow this formula:
p=mv
Where,
p = momentum
m = mass
v = </span>velocity
The cars mass is 2.0E3 and its velocity is 15m/s. Therefore:
p=2.0 x 10^3 *15 or 2000(15)
p=30000
Thus, the cars momentum is 30000 kg m/s
Faith xoxo
Answer:
.
Explanation:
If the mass of an object is 
and the velocity of that object is 
, the linear momentum of that object would be 
.
Assume that the initial velocity of the mass is positive (
.) However, the direction of the velocity is reversed after the impact. Thus, the sign of the new velocity of the object would be negative- the opposite of that of the initial velocity. The new velocity would be 
.
Thus, the change in the velocity of the mass would be:
.
The change in the linear momentum of the mass would be:
.
Thus, the magnitude of the change of the linear momentum would be 
.
