A= (70-0)/7
a=10 km/hr/sec
10 km/hr = 10 km*100 m/km/(1 hr*3=600 sec/hr)=25/9 m/sec
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a= 25/9 m/sec/sec
Hope this help, plz make brainly-est
Answer:
Apparent frequency increases for Bob and decreases for Jill.
Explanation:
Doppler effect refers to the apparent change in frequency when there is relative motion between source and the listener. When the source and listener move closer, the apparent frequency heard by the listener increases. And when the source and listener move away from each other, the apparent frequency heard by the listener decreases.
Thus, when the emergency vehicle approaches Bob, the apparent frequency of the siren increases. It moves away from Jill, the apparent frequency heard by the Jill decreases.
I think there would be 2 oxygen atoms,
If h2o is two hydrogen atoms and 1 oxygen atom then h2o has 2 potassium atoms and 1 oxygen atom, if you were to add them then together it would have 2 oxygen atoms, plz if I'm wrong correct me
Answer:
When there is no force acting on a body then a moving object move in a straight line with constant velocity and an object in rest stays in rest.
Explanation:
When there is no force acting on a body then a moving object move in a straight line with constant velocity and an object in rest stays in rest.
Answer:
1.54 kg
Explanation:
mass of first block (m) = 0.76 kg
acceleration due to gravity (g) = 9.8 m/s
what is the mass (m) of the second block
mg = kx
where m is the mass, g is the acceleration due to gravity, k is the
spring constant and x is the extension
0.76 x 9.8 = kx
7.5 = kx
k = 7.5/x ... equation 1
- when a second block is attached to the first one the amount of stretch triples (this means that extension (x) = 3x)
therefore the new mass becomes m + 0.76 and the extension
becomes 3x
with the new mass and extension, mg = kx now becomes
(m+0.76)g = k(3x) ... equation 2
Recall that k = 7.5/x from equation 1, substituting this value of k into
equation 2 we have
(m+0.76)g = 
× (3x)
(m+0.76)g = 7.5 × 3
substituting the value of g = 9.8 m/s^{2}
(m + 0.76) x 9.8 = 7.5 x 3
m + 0.76 = 22.5 ÷ 9.8
m + 0.76 = 2.3
m = 2.3 - 0.76 = 1.54 kg
